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Commit | Line | Data |
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8ae12a0d | 1 | /* |
ca632f55 | 2 | * SPI init/core code |
8ae12a0d DB |
3 | * |
4 | * Copyright (C) 2005 David Brownell | |
d57a4282 | 5 | * Copyright (C) 2008 Secret Lab Technologies Ltd. |
8ae12a0d DB |
6 | * |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License as published by | |
9 | * the Free Software Foundation; either version 2 of the License, or | |
10 | * (at your option) any later version. | |
11 | * | |
12 | * This program is distributed in the hope that it will be useful, | |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | * GNU General Public License for more details. | |
8ae12a0d DB |
16 | */ |
17 | ||
8ae12a0d DB |
18 | #include <linux/kernel.h> |
19 | #include <linux/device.h> | |
20 | #include <linux/init.h> | |
21 | #include <linux/cache.h> | |
99adef31 MB |
22 | #include <linux/dma-mapping.h> |
23 | #include <linux/dmaengine.h> | |
94040828 | 24 | #include <linux/mutex.h> |
2b7a32f7 | 25 | #include <linux/of_device.h> |
d57a4282 | 26 | #include <linux/of_irq.h> |
86be408b | 27 | #include <linux/clk/clk-conf.h> |
5a0e3ad6 | 28 | #include <linux/slab.h> |
e0626e38 | 29 | #include <linux/mod_devicetable.h> |
8ae12a0d | 30 | #include <linux/spi/spi.h> |
74317984 | 31 | #include <linux/of_gpio.h> |
3ae22e8c | 32 | #include <linux/pm_runtime.h> |
f48c767c | 33 | #include <linux/pm_domain.h> |
025ed130 | 34 | #include <linux/export.h> |
8bd75c77 | 35 | #include <linux/sched/rt.h> |
ffbbdd21 LW |
36 | #include <linux/delay.h> |
37 | #include <linux/kthread.h> | |
64bee4d2 MW |
38 | #include <linux/ioport.h> |
39 | #include <linux/acpi.h> | |
8ae12a0d | 40 | |
56ec1978 MB |
41 | #define CREATE_TRACE_POINTS |
42 | #include <trace/events/spi.h> | |
43 | ||
8ae12a0d DB |
44 | static void spidev_release(struct device *dev) |
45 | { | |
0ffa0285 | 46 | struct spi_device *spi = to_spi_device(dev); |
8ae12a0d DB |
47 | |
48 | /* spi masters may cleanup for released devices */ | |
49 | if (spi->master->cleanup) | |
50 | spi->master->cleanup(spi); | |
51 | ||
0c868461 | 52 | spi_master_put(spi->master); |
07a389fe | 53 | kfree(spi); |
8ae12a0d DB |
54 | } |
55 | ||
56 | static ssize_t | |
57 | modalias_show(struct device *dev, struct device_attribute *a, char *buf) | |
58 | { | |
59 | const struct spi_device *spi = to_spi_device(dev); | |
8c4ff6d0 ZR |
60 | int len; |
61 | ||
62 | len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1); | |
63 | if (len != -ENODEV) | |
64 | return len; | |
8ae12a0d | 65 | |
d8e328b3 | 66 | return sprintf(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias); |
8ae12a0d | 67 | } |
aa7da564 | 68 | static DEVICE_ATTR_RO(modalias); |
8ae12a0d | 69 | |
eca2ebc7 MS |
70 | #define SPI_STATISTICS_ATTRS(field, file) \ |
71 | static ssize_t spi_master_##field##_show(struct device *dev, \ | |
72 | struct device_attribute *attr, \ | |
73 | char *buf) \ | |
74 | { \ | |
75 | struct spi_master *master = container_of(dev, \ | |
76 | struct spi_master, dev); \ | |
77 | return spi_statistics_##field##_show(&master->statistics, buf); \ | |
78 | } \ | |
79 | static struct device_attribute dev_attr_spi_master_##field = { \ | |
80 | .attr = { .name = file, .mode = S_IRUGO }, \ | |
81 | .show = spi_master_##field##_show, \ | |
82 | }; \ | |
83 | static ssize_t spi_device_##field##_show(struct device *dev, \ | |
84 | struct device_attribute *attr, \ | |
85 | char *buf) \ | |
86 | { \ | |
d1eba93b | 87 | struct spi_device *spi = to_spi_device(dev); \ |
eca2ebc7 MS |
88 | return spi_statistics_##field##_show(&spi->statistics, buf); \ |
89 | } \ | |
90 | static struct device_attribute dev_attr_spi_device_##field = { \ | |
91 | .attr = { .name = file, .mode = S_IRUGO }, \ | |
92 | .show = spi_device_##field##_show, \ | |
93 | } | |
94 | ||
95 | #define SPI_STATISTICS_SHOW_NAME(name, file, field, format_string) \ | |
96 | static ssize_t spi_statistics_##name##_show(struct spi_statistics *stat, \ | |
97 | char *buf) \ | |
98 | { \ | |
99 | unsigned long flags; \ | |
100 | ssize_t len; \ | |
101 | spin_lock_irqsave(&stat->lock, flags); \ | |
102 | len = sprintf(buf, format_string, stat->field); \ | |
103 | spin_unlock_irqrestore(&stat->lock, flags); \ | |
104 | return len; \ | |
105 | } \ | |
106 | SPI_STATISTICS_ATTRS(name, file) | |
107 | ||
108 | #define SPI_STATISTICS_SHOW(field, format_string) \ | |
109 | SPI_STATISTICS_SHOW_NAME(field, __stringify(field), \ | |
110 | field, format_string) | |
111 | ||
112 | SPI_STATISTICS_SHOW(messages, "%lu"); | |
113 | SPI_STATISTICS_SHOW(transfers, "%lu"); | |
114 | SPI_STATISTICS_SHOW(errors, "%lu"); | |
115 | SPI_STATISTICS_SHOW(timedout, "%lu"); | |
116 | ||
117 | SPI_STATISTICS_SHOW(spi_sync, "%lu"); | |
118 | SPI_STATISTICS_SHOW(spi_sync_immediate, "%lu"); | |
119 | SPI_STATISTICS_SHOW(spi_async, "%lu"); | |
120 | ||
121 | SPI_STATISTICS_SHOW(bytes, "%llu"); | |
122 | SPI_STATISTICS_SHOW(bytes_rx, "%llu"); | |
123 | SPI_STATISTICS_SHOW(bytes_tx, "%llu"); | |
124 | ||
6b7bc061 MS |
125 | #define SPI_STATISTICS_TRANSFER_BYTES_HISTO(index, number) \ |
126 | SPI_STATISTICS_SHOW_NAME(transfer_bytes_histo##index, \ | |
127 | "transfer_bytes_histo_" number, \ | |
128 | transfer_bytes_histo[index], "%lu") | |
129 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(0, "0-1"); | |
130 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(1, "2-3"); | |
131 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(2, "4-7"); | |
132 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(3, "8-15"); | |
133 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(4, "16-31"); | |
134 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(5, "32-63"); | |
135 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(6, "64-127"); | |
136 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(7, "128-255"); | |
137 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(8, "256-511"); | |
138 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(9, "512-1023"); | |
139 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(10, "1024-2047"); | |
140 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(11, "2048-4095"); | |
141 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(12, "4096-8191"); | |
142 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(13, "8192-16383"); | |
143 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(14, "16384-32767"); | |
144 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(15, "32768-65535"); | |
145 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(16, "65536+"); | |
146 | ||
d9f12122 MS |
147 | SPI_STATISTICS_SHOW(transfers_split_maxsize, "%lu"); |
148 | ||
aa7da564 GKH |
149 | static struct attribute *spi_dev_attrs[] = { |
150 | &dev_attr_modalias.attr, | |
151 | NULL, | |
8ae12a0d | 152 | }; |
eca2ebc7 MS |
153 | |
154 | static const struct attribute_group spi_dev_group = { | |
155 | .attrs = spi_dev_attrs, | |
156 | }; | |
157 | ||
158 | static struct attribute *spi_device_statistics_attrs[] = { | |
159 | &dev_attr_spi_device_messages.attr, | |
160 | &dev_attr_spi_device_transfers.attr, | |
161 | &dev_attr_spi_device_errors.attr, | |
162 | &dev_attr_spi_device_timedout.attr, | |
163 | &dev_attr_spi_device_spi_sync.attr, | |
164 | &dev_attr_spi_device_spi_sync_immediate.attr, | |
165 | &dev_attr_spi_device_spi_async.attr, | |
166 | &dev_attr_spi_device_bytes.attr, | |
167 | &dev_attr_spi_device_bytes_rx.attr, | |
168 | &dev_attr_spi_device_bytes_tx.attr, | |
6b7bc061 MS |
169 | &dev_attr_spi_device_transfer_bytes_histo0.attr, |
170 | &dev_attr_spi_device_transfer_bytes_histo1.attr, | |
171 | &dev_attr_spi_device_transfer_bytes_histo2.attr, | |
172 | &dev_attr_spi_device_transfer_bytes_histo3.attr, | |
173 | &dev_attr_spi_device_transfer_bytes_histo4.attr, | |
174 | &dev_attr_spi_device_transfer_bytes_histo5.attr, | |
175 | &dev_attr_spi_device_transfer_bytes_histo6.attr, | |
176 | &dev_attr_spi_device_transfer_bytes_histo7.attr, | |
177 | &dev_attr_spi_device_transfer_bytes_histo8.attr, | |
178 | &dev_attr_spi_device_transfer_bytes_histo9.attr, | |
179 | &dev_attr_spi_device_transfer_bytes_histo10.attr, | |
180 | &dev_attr_spi_device_transfer_bytes_histo11.attr, | |
181 | &dev_attr_spi_device_transfer_bytes_histo12.attr, | |
182 | &dev_attr_spi_device_transfer_bytes_histo13.attr, | |
183 | &dev_attr_spi_device_transfer_bytes_histo14.attr, | |
184 | &dev_attr_spi_device_transfer_bytes_histo15.attr, | |
185 | &dev_attr_spi_device_transfer_bytes_histo16.attr, | |
d9f12122 | 186 | &dev_attr_spi_device_transfers_split_maxsize.attr, |
eca2ebc7 MS |
187 | NULL, |
188 | }; | |
189 | ||
190 | static const struct attribute_group spi_device_statistics_group = { | |
191 | .name = "statistics", | |
192 | .attrs = spi_device_statistics_attrs, | |
193 | }; | |
194 | ||
195 | static const struct attribute_group *spi_dev_groups[] = { | |
196 | &spi_dev_group, | |
197 | &spi_device_statistics_group, | |
198 | NULL, | |
199 | }; | |
200 | ||
201 | static struct attribute *spi_master_statistics_attrs[] = { | |
202 | &dev_attr_spi_master_messages.attr, | |
203 | &dev_attr_spi_master_transfers.attr, | |
204 | &dev_attr_spi_master_errors.attr, | |
205 | &dev_attr_spi_master_timedout.attr, | |
206 | &dev_attr_spi_master_spi_sync.attr, | |
207 | &dev_attr_spi_master_spi_sync_immediate.attr, | |
208 | &dev_attr_spi_master_spi_async.attr, | |
209 | &dev_attr_spi_master_bytes.attr, | |
210 | &dev_attr_spi_master_bytes_rx.attr, | |
211 | &dev_attr_spi_master_bytes_tx.attr, | |
6b7bc061 MS |
212 | &dev_attr_spi_master_transfer_bytes_histo0.attr, |
213 | &dev_attr_spi_master_transfer_bytes_histo1.attr, | |
214 | &dev_attr_spi_master_transfer_bytes_histo2.attr, | |
215 | &dev_attr_spi_master_transfer_bytes_histo3.attr, | |
216 | &dev_attr_spi_master_transfer_bytes_histo4.attr, | |
217 | &dev_attr_spi_master_transfer_bytes_histo5.attr, | |
218 | &dev_attr_spi_master_transfer_bytes_histo6.attr, | |
219 | &dev_attr_spi_master_transfer_bytes_histo7.attr, | |
220 | &dev_attr_spi_master_transfer_bytes_histo8.attr, | |
221 | &dev_attr_spi_master_transfer_bytes_histo9.attr, | |
222 | &dev_attr_spi_master_transfer_bytes_histo10.attr, | |
223 | &dev_attr_spi_master_transfer_bytes_histo11.attr, | |
224 | &dev_attr_spi_master_transfer_bytes_histo12.attr, | |
225 | &dev_attr_spi_master_transfer_bytes_histo13.attr, | |
226 | &dev_attr_spi_master_transfer_bytes_histo14.attr, | |
227 | &dev_attr_spi_master_transfer_bytes_histo15.attr, | |
228 | &dev_attr_spi_master_transfer_bytes_histo16.attr, | |
d9f12122 | 229 | &dev_attr_spi_master_transfers_split_maxsize.attr, |
eca2ebc7 MS |
230 | NULL, |
231 | }; | |
232 | ||
233 | static const struct attribute_group spi_master_statistics_group = { | |
234 | .name = "statistics", | |
235 | .attrs = spi_master_statistics_attrs, | |
236 | }; | |
237 | ||
238 | static const struct attribute_group *spi_master_groups[] = { | |
239 | &spi_master_statistics_group, | |
240 | NULL, | |
241 | }; | |
242 | ||
243 | void spi_statistics_add_transfer_stats(struct spi_statistics *stats, | |
244 | struct spi_transfer *xfer, | |
245 | struct spi_master *master) | |
246 | { | |
247 | unsigned long flags; | |
6b7bc061 MS |
248 | int l2len = min(fls(xfer->len), SPI_STATISTICS_HISTO_SIZE) - 1; |
249 | ||
250 | if (l2len < 0) | |
251 | l2len = 0; | |
eca2ebc7 MS |
252 | |
253 | spin_lock_irqsave(&stats->lock, flags); | |
254 | ||
255 | stats->transfers++; | |
6b7bc061 | 256 | stats->transfer_bytes_histo[l2len]++; |
eca2ebc7 MS |
257 | |
258 | stats->bytes += xfer->len; | |
259 | if ((xfer->tx_buf) && | |
260 | (xfer->tx_buf != master->dummy_tx)) | |
261 | stats->bytes_tx += xfer->len; | |
262 | if ((xfer->rx_buf) && | |
263 | (xfer->rx_buf != master->dummy_rx)) | |
264 | stats->bytes_rx += xfer->len; | |
265 | ||
266 | spin_unlock_irqrestore(&stats->lock, flags); | |
267 | } | |
268 | EXPORT_SYMBOL_GPL(spi_statistics_add_transfer_stats); | |
8ae12a0d DB |
269 | |
270 | /* modalias support makes "modprobe $MODALIAS" new-style hotplug work, | |
271 | * and the sysfs version makes coldplug work too. | |
272 | */ | |
273 | ||
75368bf6 AV |
274 | static const struct spi_device_id *spi_match_id(const struct spi_device_id *id, |
275 | const struct spi_device *sdev) | |
276 | { | |
277 | while (id->name[0]) { | |
278 | if (!strcmp(sdev->modalias, id->name)) | |
279 | return id; | |
280 | id++; | |
281 | } | |
282 | return NULL; | |
283 | } | |
284 | ||
285 | const struct spi_device_id *spi_get_device_id(const struct spi_device *sdev) | |
286 | { | |
287 | const struct spi_driver *sdrv = to_spi_driver(sdev->dev.driver); | |
288 | ||
289 | return spi_match_id(sdrv->id_table, sdev); | |
290 | } | |
291 | EXPORT_SYMBOL_GPL(spi_get_device_id); | |
292 | ||
8ae12a0d DB |
293 | static int spi_match_device(struct device *dev, struct device_driver *drv) |
294 | { | |
295 | const struct spi_device *spi = to_spi_device(dev); | |
75368bf6 AV |
296 | const struct spi_driver *sdrv = to_spi_driver(drv); |
297 | ||
2b7a32f7 SA |
298 | /* Attempt an OF style match */ |
299 | if (of_driver_match_device(dev, drv)) | |
300 | return 1; | |
301 | ||
64bee4d2 MW |
302 | /* Then try ACPI */ |
303 | if (acpi_driver_match_device(dev, drv)) | |
304 | return 1; | |
305 | ||
75368bf6 AV |
306 | if (sdrv->id_table) |
307 | return !!spi_match_id(sdrv->id_table, spi); | |
8ae12a0d | 308 | |
35f74fca | 309 | return strcmp(spi->modalias, drv->name) == 0; |
8ae12a0d DB |
310 | } |
311 | ||
7eff2e7a | 312 | static int spi_uevent(struct device *dev, struct kobj_uevent_env *env) |
8ae12a0d DB |
313 | { |
314 | const struct spi_device *spi = to_spi_device(dev); | |
8c4ff6d0 ZR |
315 | int rc; |
316 | ||
317 | rc = acpi_device_uevent_modalias(dev, env); | |
318 | if (rc != -ENODEV) | |
319 | return rc; | |
8ae12a0d | 320 | |
e0626e38 | 321 | add_uevent_var(env, "MODALIAS=%s%s", SPI_MODULE_PREFIX, spi->modalias); |
8ae12a0d DB |
322 | return 0; |
323 | } | |
324 | ||
8ae12a0d DB |
325 | struct bus_type spi_bus_type = { |
326 | .name = "spi", | |
aa7da564 | 327 | .dev_groups = spi_dev_groups, |
8ae12a0d DB |
328 | .match = spi_match_device, |
329 | .uevent = spi_uevent, | |
8ae12a0d DB |
330 | }; |
331 | EXPORT_SYMBOL_GPL(spi_bus_type); | |
332 | ||
b885244e DB |
333 | |
334 | static int spi_drv_probe(struct device *dev) | |
335 | { | |
336 | const struct spi_driver *sdrv = to_spi_driver(dev->driver); | |
44af7927 | 337 | struct spi_device *spi = to_spi_device(dev); |
33cf00e5 MW |
338 | int ret; |
339 | ||
86be408b SN |
340 | ret = of_clk_set_defaults(dev->of_node, false); |
341 | if (ret) | |
342 | return ret; | |
343 | ||
44af7927 JH |
344 | if (dev->of_node) { |
345 | spi->irq = of_irq_get(dev->of_node, 0); | |
346 | if (spi->irq == -EPROBE_DEFER) | |
347 | return -EPROBE_DEFER; | |
348 | if (spi->irq < 0) | |
349 | spi->irq = 0; | |
350 | } | |
351 | ||
676e7c25 UH |
352 | ret = dev_pm_domain_attach(dev, true); |
353 | if (ret != -EPROBE_DEFER) { | |
44af7927 | 354 | ret = sdrv->probe(spi); |
676e7c25 UH |
355 | if (ret) |
356 | dev_pm_domain_detach(dev, true); | |
357 | } | |
b885244e | 358 | |
33cf00e5 | 359 | return ret; |
b885244e DB |
360 | } |
361 | ||
362 | static int spi_drv_remove(struct device *dev) | |
363 | { | |
364 | const struct spi_driver *sdrv = to_spi_driver(dev->driver); | |
33cf00e5 MW |
365 | int ret; |
366 | ||
aec35f4e | 367 | ret = sdrv->remove(to_spi_device(dev)); |
676e7c25 | 368 | dev_pm_domain_detach(dev, true); |
b885244e | 369 | |
33cf00e5 | 370 | return ret; |
b885244e DB |
371 | } |
372 | ||
373 | static void spi_drv_shutdown(struct device *dev) | |
374 | { | |
375 | const struct spi_driver *sdrv = to_spi_driver(dev->driver); | |
376 | ||
377 | sdrv->shutdown(to_spi_device(dev)); | |
378 | } | |
379 | ||
33e34dc6 | 380 | /** |
ca5d2485 | 381 | * __spi_register_driver - register a SPI driver |
88c9321d | 382 | * @owner: owner module of the driver to register |
33e34dc6 DB |
383 | * @sdrv: the driver to register |
384 | * Context: can sleep | |
97d56dc6 JMC |
385 | * |
386 | * Return: zero on success, else a negative error code. | |
33e34dc6 | 387 | */ |
ca5d2485 | 388 | int __spi_register_driver(struct module *owner, struct spi_driver *sdrv) |
b885244e | 389 | { |
ca5d2485 | 390 | sdrv->driver.owner = owner; |
b885244e DB |
391 | sdrv->driver.bus = &spi_bus_type; |
392 | if (sdrv->probe) | |
393 | sdrv->driver.probe = spi_drv_probe; | |
394 | if (sdrv->remove) | |
395 | sdrv->driver.remove = spi_drv_remove; | |
396 | if (sdrv->shutdown) | |
397 | sdrv->driver.shutdown = spi_drv_shutdown; | |
398 | return driver_register(&sdrv->driver); | |
399 | } | |
ca5d2485 | 400 | EXPORT_SYMBOL_GPL(__spi_register_driver); |
b885244e | 401 | |
8ae12a0d DB |
402 | /*-------------------------------------------------------------------------*/ |
403 | ||
404 | /* SPI devices should normally not be created by SPI device drivers; that | |
405 | * would make them board-specific. Similarly with SPI master drivers. | |
406 | * Device registration normally goes into like arch/.../mach.../board-YYY.c | |
407 | * with other readonly (flashable) information about mainboard devices. | |
408 | */ | |
409 | ||
410 | struct boardinfo { | |
411 | struct list_head list; | |
2b9603a0 | 412 | struct spi_board_info board_info; |
8ae12a0d DB |
413 | }; |
414 | ||
415 | static LIST_HEAD(board_list); | |
2b9603a0 FT |
416 | static LIST_HEAD(spi_master_list); |
417 | ||
418 | /* | |
419 | * Used to protect add/del opertion for board_info list and | |
420 | * spi_master list, and their matching process | |
421 | */ | |
94040828 | 422 | static DEFINE_MUTEX(board_lock); |
8ae12a0d | 423 | |
dc87c98e GL |
424 | /** |
425 | * spi_alloc_device - Allocate a new SPI device | |
426 | * @master: Controller to which device is connected | |
427 | * Context: can sleep | |
428 | * | |
429 | * Allows a driver to allocate and initialize a spi_device without | |
430 | * registering it immediately. This allows a driver to directly | |
431 | * fill the spi_device with device parameters before calling | |
432 | * spi_add_device() on it. | |
433 | * | |
434 | * Caller is responsible to call spi_add_device() on the returned | |
435 | * spi_device structure to add it to the SPI master. If the caller | |
436 | * needs to discard the spi_device without adding it, then it should | |
437 | * call spi_dev_put() on it. | |
438 | * | |
97d56dc6 | 439 | * Return: a pointer to the new device, or NULL. |
dc87c98e GL |
440 | */ |
441 | struct spi_device *spi_alloc_device(struct spi_master *master) | |
442 | { | |
443 | struct spi_device *spi; | |
dc87c98e GL |
444 | |
445 | if (!spi_master_get(master)) | |
446 | return NULL; | |
447 | ||
5fe5f05e | 448 | spi = kzalloc(sizeof(*spi), GFP_KERNEL); |
dc87c98e | 449 | if (!spi) { |
dc87c98e GL |
450 | spi_master_put(master); |
451 | return NULL; | |
452 | } | |
453 | ||
454 | spi->master = master; | |
178db7d3 | 455 | spi->dev.parent = &master->dev; |
dc87c98e GL |
456 | spi->dev.bus = &spi_bus_type; |
457 | spi->dev.release = spidev_release; | |
446411e1 | 458 | spi->cs_gpio = -ENOENT; |
eca2ebc7 MS |
459 | |
460 | spin_lock_init(&spi->statistics.lock); | |
461 | ||
dc87c98e GL |
462 | device_initialize(&spi->dev); |
463 | return spi; | |
464 | } | |
465 | EXPORT_SYMBOL_GPL(spi_alloc_device); | |
466 | ||
e13ac47b JN |
467 | static void spi_dev_set_name(struct spi_device *spi) |
468 | { | |
469 | struct acpi_device *adev = ACPI_COMPANION(&spi->dev); | |
470 | ||
471 | if (adev) { | |
472 | dev_set_name(&spi->dev, "spi-%s", acpi_dev_name(adev)); | |
473 | return; | |
474 | } | |
475 | ||
476 | dev_set_name(&spi->dev, "%s.%u", dev_name(&spi->master->dev), | |
477 | spi->chip_select); | |
478 | } | |
479 | ||
b6fb8d3a MW |
480 | static int spi_dev_check(struct device *dev, void *data) |
481 | { | |
482 | struct spi_device *spi = to_spi_device(dev); | |
483 | struct spi_device *new_spi = data; | |
484 | ||
485 | if (spi->master == new_spi->master && | |
486 | spi->chip_select == new_spi->chip_select) | |
487 | return -EBUSY; | |
488 | return 0; | |
489 | } | |
490 | ||
dc87c98e GL |
491 | /** |
492 | * spi_add_device - Add spi_device allocated with spi_alloc_device | |
493 | * @spi: spi_device to register | |
494 | * | |
495 | * Companion function to spi_alloc_device. Devices allocated with | |
496 | * spi_alloc_device can be added onto the spi bus with this function. | |
497 | * | |
97d56dc6 | 498 | * Return: 0 on success; negative errno on failure |
dc87c98e GL |
499 | */ |
500 | int spi_add_device(struct spi_device *spi) | |
501 | { | |
e48880e0 | 502 | static DEFINE_MUTEX(spi_add_lock); |
74317984 JCPV |
503 | struct spi_master *master = spi->master; |
504 | struct device *dev = master->dev.parent; | |
dc87c98e GL |
505 | int status; |
506 | ||
507 | /* Chipselects are numbered 0..max; validate. */ | |
74317984 | 508 | if (spi->chip_select >= master->num_chipselect) { |
dc87c98e GL |
509 | dev_err(dev, "cs%d >= max %d\n", |
510 | spi->chip_select, | |
74317984 | 511 | master->num_chipselect); |
dc87c98e GL |
512 | return -EINVAL; |
513 | } | |
514 | ||
515 | /* Set the bus ID string */ | |
e13ac47b | 516 | spi_dev_set_name(spi); |
e48880e0 DB |
517 | |
518 | /* We need to make sure there's no other device with this | |
519 | * chipselect **BEFORE** we call setup(), else we'll trash | |
520 | * its configuration. Lock against concurrent add() calls. | |
521 | */ | |
522 | mutex_lock(&spi_add_lock); | |
523 | ||
b6fb8d3a MW |
524 | status = bus_for_each_dev(&spi_bus_type, NULL, spi, spi_dev_check); |
525 | if (status) { | |
e48880e0 DB |
526 | dev_err(dev, "chipselect %d already in use\n", |
527 | spi->chip_select); | |
e48880e0 DB |
528 | goto done; |
529 | } | |
530 | ||
74317984 JCPV |
531 | if (master->cs_gpios) |
532 | spi->cs_gpio = master->cs_gpios[spi->chip_select]; | |
533 | ||
e48880e0 DB |
534 | /* Drivers may modify this initial i/o setup, but will |
535 | * normally rely on the device being setup. Devices | |
536 | * using SPI_CS_HIGH can't coexist well otherwise... | |
537 | */ | |
7d077197 | 538 | status = spi_setup(spi); |
dc87c98e | 539 | if (status < 0) { |
eb288a1f LW |
540 | dev_err(dev, "can't setup %s, status %d\n", |
541 | dev_name(&spi->dev), status); | |
e48880e0 | 542 | goto done; |
dc87c98e GL |
543 | } |
544 | ||
e48880e0 | 545 | /* Device may be bound to an active driver when this returns */ |
dc87c98e | 546 | status = device_add(&spi->dev); |
e48880e0 | 547 | if (status < 0) |
eb288a1f LW |
548 | dev_err(dev, "can't add %s, status %d\n", |
549 | dev_name(&spi->dev), status); | |
e48880e0 | 550 | else |
35f74fca | 551 | dev_dbg(dev, "registered child %s\n", dev_name(&spi->dev)); |
dc87c98e | 552 | |
e48880e0 DB |
553 | done: |
554 | mutex_unlock(&spi_add_lock); | |
555 | return status; | |
dc87c98e GL |
556 | } |
557 | EXPORT_SYMBOL_GPL(spi_add_device); | |
8ae12a0d | 558 | |
33e34dc6 DB |
559 | /** |
560 | * spi_new_device - instantiate one new SPI device | |
561 | * @master: Controller to which device is connected | |
562 | * @chip: Describes the SPI device | |
563 | * Context: can sleep | |
564 | * | |
565 | * On typical mainboards, this is purely internal; and it's not needed | |
8ae12a0d DB |
566 | * after board init creates the hard-wired devices. Some development |
567 | * platforms may not be able to use spi_register_board_info though, and | |
568 | * this is exported so that for example a USB or parport based adapter | |
569 | * driver could add devices (which it would learn about out-of-band). | |
082c8cb4 | 570 | * |
97d56dc6 | 571 | * Return: the new device, or NULL. |
8ae12a0d | 572 | */ |
e9d5a461 AB |
573 | struct spi_device *spi_new_device(struct spi_master *master, |
574 | struct spi_board_info *chip) | |
8ae12a0d DB |
575 | { |
576 | struct spi_device *proxy; | |
8ae12a0d DB |
577 | int status; |
578 | ||
082c8cb4 DB |
579 | /* NOTE: caller did any chip->bus_num checks necessary. |
580 | * | |
581 | * Also, unless we change the return value convention to use | |
582 | * error-or-pointer (not NULL-or-pointer), troubleshootability | |
583 | * suggests syslogged diagnostics are best here (ugh). | |
584 | */ | |
585 | ||
dc87c98e GL |
586 | proxy = spi_alloc_device(master); |
587 | if (!proxy) | |
8ae12a0d DB |
588 | return NULL; |
589 | ||
102eb975 GL |
590 | WARN_ON(strlen(chip->modalias) >= sizeof(proxy->modalias)); |
591 | ||
8ae12a0d DB |
592 | proxy->chip_select = chip->chip_select; |
593 | proxy->max_speed_hz = chip->max_speed_hz; | |
980a01c9 | 594 | proxy->mode = chip->mode; |
8ae12a0d | 595 | proxy->irq = chip->irq; |
102eb975 | 596 | strlcpy(proxy->modalias, chip->modalias, sizeof(proxy->modalias)); |
8ae12a0d DB |
597 | proxy->dev.platform_data = (void *) chip->platform_data; |
598 | proxy->controller_data = chip->controller_data; | |
599 | proxy->controller_state = NULL; | |
8ae12a0d | 600 | |
dc87c98e | 601 | status = spi_add_device(proxy); |
8ae12a0d | 602 | if (status < 0) { |
dc87c98e GL |
603 | spi_dev_put(proxy); |
604 | return NULL; | |
8ae12a0d DB |
605 | } |
606 | ||
8ae12a0d DB |
607 | return proxy; |
608 | } | |
609 | EXPORT_SYMBOL_GPL(spi_new_device); | |
610 | ||
3b1884c2 GU |
611 | /** |
612 | * spi_unregister_device - unregister a single SPI device | |
613 | * @spi: spi_device to unregister | |
614 | * | |
615 | * Start making the passed SPI device vanish. Normally this would be handled | |
616 | * by spi_unregister_master(). | |
617 | */ | |
618 | void spi_unregister_device(struct spi_device *spi) | |
619 | { | |
bd6c1644 GU |
620 | if (!spi) |
621 | return; | |
622 | ||
623 | if (spi->dev.of_node) | |
624 | of_node_clear_flag(spi->dev.of_node, OF_POPULATED); | |
625 | device_unregister(&spi->dev); | |
3b1884c2 GU |
626 | } |
627 | EXPORT_SYMBOL_GPL(spi_unregister_device); | |
628 | ||
2b9603a0 FT |
629 | static void spi_match_master_to_boardinfo(struct spi_master *master, |
630 | struct spi_board_info *bi) | |
631 | { | |
632 | struct spi_device *dev; | |
633 | ||
634 | if (master->bus_num != bi->bus_num) | |
635 | return; | |
636 | ||
637 | dev = spi_new_device(master, bi); | |
638 | if (!dev) | |
639 | dev_err(master->dev.parent, "can't create new device for %s\n", | |
640 | bi->modalias); | |
641 | } | |
642 | ||
33e34dc6 DB |
643 | /** |
644 | * spi_register_board_info - register SPI devices for a given board | |
645 | * @info: array of chip descriptors | |
646 | * @n: how many descriptors are provided | |
647 | * Context: can sleep | |
648 | * | |
8ae12a0d DB |
649 | * Board-specific early init code calls this (probably during arch_initcall) |
650 | * with segments of the SPI device table. Any device nodes are created later, | |
651 | * after the relevant parent SPI controller (bus_num) is defined. We keep | |
652 | * this table of devices forever, so that reloading a controller driver will | |
653 | * not make Linux forget about these hard-wired devices. | |
654 | * | |
655 | * Other code can also call this, e.g. a particular add-on board might provide | |
656 | * SPI devices through its expansion connector, so code initializing that board | |
657 | * would naturally declare its SPI devices. | |
658 | * | |
659 | * The board info passed can safely be __initdata ... but be careful of | |
660 | * any embedded pointers (platform_data, etc), they're copied as-is. | |
97d56dc6 JMC |
661 | * |
662 | * Return: zero on success, else a negative error code. | |
8ae12a0d | 663 | */ |
fd4a319b | 664 | int spi_register_board_info(struct spi_board_info const *info, unsigned n) |
8ae12a0d | 665 | { |
2b9603a0 FT |
666 | struct boardinfo *bi; |
667 | int i; | |
8ae12a0d | 668 | |
c7908a37 XL |
669 | if (!n) |
670 | return -EINVAL; | |
671 | ||
2b9603a0 | 672 | bi = kzalloc(n * sizeof(*bi), GFP_KERNEL); |
8ae12a0d DB |
673 | if (!bi) |
674 | return -ENOMEM; | |
8ae12a0d | 675 | |
2b9603a0 FT |
676 | for (i = 0; i < n; i++, bi++, info++) { |
677 | struct spi_master *master; | |
8ae12a0d | 678 | |
2b9603a0 FT |
679 | memcpy(&bi->board_info, info, sizeof(*info)); |
680 | mutex_lock(&board_lock); | |
681 | list_add_tail(&bi->list, &board_list); | |
682 | list_for_each_entry(master, &spi_master_list, list) | |
683 | spi_match_master_to_boardinfo(master, &bi->board_info); | |
684 | mutex_unlock(&board_lock); | |
8ae12a0d | 685 | } |
2b9603a0 FT |
686 | |
687 | return 0; | |
8ae12a0d DB |
688 | } |
689 | ||
690 | /*-------------------------------------------------------------------------*/ | |
691 | ||
b158935f MB |
692 | static void spi_set_cs(struct spi_device *spi, bool enable) |
693 | { | |
694 | if (spi->mode & SPI_CS_HIGH) | |
695 | enable = !enable; | |
696 | ||
243f07be | 697 | if (gpio_is_valid(spi->cs_gpio)) |
b158935f MB |
698 | gpio_set_value(spi->cs_gpio, !enable); |
699 | else if (spi->master->set_cs) | |
700 | spi->master->set_cs(spi, !enable); | |
701 | } | |
702 | ||
2de440f5 | 703 | #ifdef CONFIG_HAS_DMA |
6ad45a27 MB |
704 | static int spi_map_buf(struct spi_master *master, struct device *dev, |
705 | struct sg_table *sgt, void *buf, size_t len, | |
706 | enum dma_data_direction dir) | |
707 | { | |
708 | const bool vmalloced_buf = is_vmalloc_addr(buf); | |
65598c13 AG |
709 | int desc_len; |
710 | int sgs; | |
6ad45a27 MB |
711 | struct page *vm_page; |
712 | void *sg_buf; | |
713 | size_t min; | |
714 | int i, ret; | |
715 | ||
65598c13 AG |
716 | if (vmalloced_buf) { |
717 | desc_len = PAGE_SIZE; | |
718 | sgs = DIV_ROUND_UP(len + offset_in_page(buf), desc_len); | |
719 | } else { | |
720 | desc_len = master->max_dma_len; | |
721 | sgs = DIV_ROUND_UP(len, desc_len); | |
722 | } | |
723 | ||
6ad45a27 MB |
724 | ret = sg_alloc_table(sgt, sgs, GFP_KERNEL); |
725 | if (ret != 0) | |
726 | return ret; | |
727 | ||
728 | for (i = 0; i < sgs; i++) { | |
6ad45a27 MB |
729 | |
730 | if (vmalloced_buf) { | |
65598c13 AG |
731 | min = min_t(size_t, |
732 | len, desc_len - offset_in_page(buf)); | |
6ad45a27 MB |
733 | vm_page = vmalloc_to_page(buf); |
734 | if (!vm_page) { | |
735 | sg_free_table(sgt); | |
736 | return -ENOMEM; | |
737 | } | |
c1aefbdd CK |
738 | sg_set_page(&sgt->sgl[i], vm_page, |
739 | min, offset_in_page(buf)); | |
6ad45a27 | 740 | } else { |
65598c13 | 741 | min = min_t(size_t, len, desc_len); |
6ad45a27 | 742 | sg_buf = buf; |
c1aefbdd | 743 | sg_set_buf(&sgt->sgl[i], sg_buf, min); |
6ad45a27 MB |
744 | } |
745 | ||
6ad45a27 MB |
746 | |
747 | buf += min; | |
748 | len -= min; | |
749 | } | |
750 | ||
751 | ret = dma_map_sg(dev, sgt->sgl, sgt->nents, dir); | |
89e4b66a GU |
752 | if (!ret) |
753 | ret = -ENOMEM; | |
6ad45a27 MB |
754 | if (ret < 0) { |
755 | sg_free_table(sgt); | |
756 | return ret; | |
757 | } | |
758 | ||
759 | sgt->nents = ret; | |
760 | ||
761 | return 0; | |
762 | } | |
763 | ||
764 | static void spi_unmap_buf(struct spi_master *master, struct device *dev, | |
765 | struct sg_table *sgt, enum dma_data_direction dir) | |
766 | { | |
767 | if (sgt->orig_nents) { | |
768 | dma_unmap_sg(dev, sgt->sgl, sgt->orig_nents, dir); | |
769 | sg_free_table(sgt); | |
770 | } | |
771 | } | |
772 | ||
2de440f5 | 773 | static int __spi_map_msg(struct spi_master *master, struct spi_message *msg) |
99adef31 | 774 | { |
99adef31 MB |
775 | struct device *tx_dev, *rx_dev; |
776 | struct spi_transfer *xfer; | |
6ad45a27 | 777 | int ret; |
3a2eba9b | 778 | |
6ad45a27 | 779 | if (!master->can_dma) |
99adef31 MB |
780 | return 0; |
781 | ||
c37f45b5 LL |
782 | if (master->dma_tx) |
783 | tx_dev = master->dma_tx->device->dev; | |
784 | else | |
785 | tx_dev = &master->dev; | |
786 | ||
787 | if (master->dma_rx) | |
788 | rx_dev = master->dma_rx->device->dev; | |
789 | else | |
790 | rx_dev = &master->dev; | |
99adef31 MB |
791 | |
792 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | |
793 | if (!master->can_dma(master, msg->spi, xfer)) | |
794 | continue; | |
795 | ||
796 | if (xfer->tx_buf != NULL) { | |
6ad45a27 MB |
797 | ret = spi_map_buf(master, tx_dev, &xfer->tx_sg, |
798 | (void *)xfer->tx_buf, xfer->len, | |
799 | DMA_TO_DEVICE); | |
800 | if (ret != 0) | |
801 | return ret; | |
99adef31 MB |
802 | } |
803 | ||
804 | if (xfer->rx_buf != NULL) { | |
6ad45a27 MB |
805 | ret = spi_map_buf(master, rx_dev, &xfer->rx_sg, |
806 | xfer->rx_buf, xfer->len, | |
807 | DMA_FROM_DEVICE); | |
808 | if (ret != 0) { | |
809 | spi_unmap_buf(master, tx_dev, &xfer->tx_sg, | |
810 | DMA_TO_DEVICE); | |
811 | return ret; | |
99adef31 MB |
812 | } |
813 | } | |
814 | } | |
815 | ||
816 | master->cur_msg_mapped = true; | |
817 | ||
818 | return 0; | |
819 | } | |
820 | ||
4b786458 | 821 | static int __spi_unmap_msg(struct spi_master *master, struct spi_message *msg) |
99adef31 MB |
822 | { |
823 | struct spi_transfer *xfer; | |
824 | struct device *tx_dev, *rx_dev; | |
825 | ||
6ad45a27 | 826 | if (!master->cur_msg_mapped || !master->can_dma) |
99adef31 MB |
827 | return 0; |
828 | ||
c37f45b5 LL |
829 | if (master->dma_tx) |
830 | tx_dev = master->dma_tx->device->dev; | |
831 | else | |
832 | tx_dev = &master->dev; | |
833 | ||
834 | if (master->dma_rx) | |
835 | rx_dev = master->dma_rx->device->dev; | |
836 | else | |
837 | rx_dev = &master->dev; | |
99adef31 MB |
838 | |
839 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | |
840 | if (!master->can_dma(master, msg->spi, xfer)) | |
841 | continue; | |
842 | ||
6ad45a27 MB |
843 | spi_unmap_buf(master, rx_dev, &xfer->rx_sg, DMA_FROM_DEVICE); |
844 | spi_unmap_buf(master, tx_dev, &xfer->tx_sg, DMA_TO_DEVICE); | |
99adef31 MB |
845 | } |
846 | ||
847 | return 0; | |
848 | } | |
2de440f5 GU |
849 | #else /* !CONFIG_HAS_DMA */ |
850 | static inline int __spi_map_msg(struct spi_master *master, | |
851 | struct spi_message *msg) | |
852 | { | |
853 | return 0; | |
854 | } | |
855 | ||
4b786458 MS |
856 | static inline int __spi_unmap_msg(struct spi_master *master, |
857 | struct spi_message *msg) | |
2de440f5 GU |
858 | { |
859 | return 0; | |
860 | } | |
861 | #endif /* !CONFIG_HAS_DMA */ | |
862 | ||
4b786458 MS |
863 | static inline int spi_unmap_msg(struct spi_master *master, |
864 | struct spi_message *msg) | |
865 | { | |
866 | struct spi_transfer *xfer; | |
867 | ||
868 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | |
869 | /* | |
870 | * Restore the original value of tx_buf or rx_buf if they are | |
871 | * NULL. | |
872 | */ | |
873 | if (xfer->tx_buf == master->dummy_tx) | |
874 | xfer->tx_buf = NULL; | |
875 | if (xfer->rx_buf == master->dummy_rx) | |
876 | xfer->rx_buf = NULL; | |
877 | } | |
878 | ||
879 | return __spi_unmap_msg(master, msg); | |
880 | } | |
881 | ||
2de440f5 GU |
882 | static int spi_map_msg(struct spi_master *master, struct spi_message *msg) |
883 | { | |
884 | struct spi_transfer *xfer; | |
885 | void *tmp; | |
886 | unsigned int max_tx, max_rx; | |
887 | ||
888 | if (master->flags & (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX)) { | |
889 | max_tx = 0; | |
890 | max_rx = 0; | |
891 | ||
892 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | |
893 | if ((master->flags & SPI_MASTER_MUST_TX) && | |
894 | !xfer->tx_buf) | |
895 | max_tx = max(xfer->len, max_tx); | |
896 | if ((master->flags & SPI_MASTER_MUST_RX) && | |
897 | !xfer->rx_buf) | |
898 | max_rx = max(xfer->len, max_rx); | |
899 | } | |
900 | ||
901 | if (max_tx) { | |
902 | tmp = krealloc(master->dummy_tx, max_tx, | |
903 | GFP_KERNEL | GFP_DMA); | |
904 | if (!tmp) | |
905 | return -ENOMEM; | |
906 | master->dummy_tx = tmp; | |
907 | memset(tmp, 0, max_tx); | |
908 | } | |
909 | ||
910 | if (max_rx) { | |
911 | tmp = krealloc(master->dummy_rx, max_rx, | |
912 | GFP_KERNEL | GFP_DMA); | |
913 | if (!tmp) | |
914 | return -ENOMEM; | |
915 | master->dummy_rx = tmp; | |
916 | } | |
917 | ||
918 | if (max_tx || max_rx) { | |
919 | list_for_each_entry(xfer, &msg->transfers, | |
920 | transfer_list) { | |
921 | if (!xfer->tx_buf) | |
922 | xfer->tx_buf = master->dummy_tx; | |
923 | if (!xfer->rx_buf) | |
924 | xfer->rx_buf = master->dummy_rx; | |
925 | } | |
926 | } | |
927 | } | |
928 | ||
929 | return __spi_map_msg(master, msg); | |
930 | } | |
99adef31 | 931 | |
b158935f MB |
932 | /* |
933 | * spi_transfer_one_message - Default implementation of transfer_one_message() | |
934 | * | |
935 | * This is a standard implementation of transfer_one_message() for | |
936 | * drivers which impelment a transfer_one() operation. It provides | |
937 | * standard handling of delays and chip select management. | |
938 | */ | |
939 | static int spi_transfer_one_message(struct spi_master *master, | |
940 | struct spi_message *msg) | |
941 | { | |
942 | struct spi_transfer *xfer; | |
b158935f MB |
943 | bool keep_cs = false; |
944 | int ret = 0; | |
682a71b2 | 945 | unsigned long ms = 1; |
eca2ebc7 MS |
946 | struct spi_statistics *statm = &master->statistics; |
947 | struct spi_statistics *stats = &msg->spi->statistics; | |
b158935f MB |
948 | |
949 | spi_set_cs(msg->spi, true); | |
950 | ||
eca2ebc7 MS |
951 | SPI_STATISTICS_INCREMENT_FIELD(statm, messages); |
952 | SPI_STATISTICS_INCREMENT_FIELD(stats, messages); | |
953 | ||
b158935f MB |
954 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { |
955 | trace_spi_transfer_start(msg, xfer); | |
956 | ||
eca2ebc7 MS |
957 | spi_statistics_add_transfer_stats(statm, xfer, master); |
958 | spi_statistics_add_transfer_stats(stats, xfer, master); | |
959 | ||
38ec10f6 MB |
960 | if (xfer->tx_buf || xfer->rx_buf) { |
961 | reinit_completion(&master->xfer_completion); | |
b158935f | 962 | |
38ec10f6 MB |
963 | ret = master->transfer_one(master, msg->spi, xfer); |
964 | if (ret < 0) { | |
eca2ebc7 MS |
965 | SPI_STATISTICS_INCREMENT_FIELD(statm, |
966 | errors); | |
967 | SPI_STATISTICS_INCREMENT_FIELD(stats, | |
968 | errors); | |
38ec10f6 MB |
969 | dev_err(&msg->spi->dev, |
970 | "SPI transfer failed: %d\n", ret); | |
971 | goto out; | |
972 | } | |
b158935f | 973 | |
38ec10f6 MB |
974 | if (ret > 0) { |
975 | ret = 0; | |
976 | ms = xfer->len * 8 * 1000 / xfer->speed_hz; | |
977 | ms += ms + 100; /* some tolerance */ | |
16a0ce4e | 978 | |
38ec10f6 MB |
979 | ms = wait_for_completion_timeout(&master->xfer_completion, |
980 | msecs_to_jiffies(ms)); | |
981 | } | |
16a0ce4e | 982 | |
38ec10f6 | 983 | if (ms == 0) { |
eca2ebc7 MS |
984 | SPI_STATISTICS_INCREMENT_FIELD(statm, |
985 | timedout); | |
986 | SPI_STATISTICS_INCREMENT_FIELD(stats, | |
987 | timedout); | |
38ec10f6 MB |
988 | dev_err(&msg->spi->dev, |
989 | "SPI transfer timed out\n"); | |
990 | msg->status = -ETIMEDOUT; | |
991 | } | |
992 | } else { | |
993 | if (xfer->len) | |
994 | dev_err(&msg->spi->dev, | |
995 | "Bufferless transfer has length %u\n", | |
996 | xfer->len); | |
13a42798 | 997 | } |
b158935f MB |
998 | |
999 | trace_spi_transfer_stop(msg, xfer); | |
1000 | ||
1001 | if (msg->status != -EINPROGRESS) | |
1002 | goto out; | |
1003 | ||
1004 | if (xfer->delay_usecs) | |
1005 | udelay(xfer->delay_usecs); | |
1006 | ||
1007 | if (xfer->cs_change) { | |
1008 | if (list_is_last(&xfer->transfer_list, | |
1009 | &msg->transfers)) { | |
1010 | keep_cs = true; | |
1011 | } else { | |
0b73aa63 MB |
1012 | spi_set_cs(msg->spi, false); |
1013 | udelay(10); | |
1014 | spi_set_cs(msg->spi, true); | |
b158935f MB |
1015 | } |
1016 | } | |
1017 | ||
1018 | msg->actual_length += xfer->len; | |
1019 | } | |
1020 | ||
1021 | out: | |
1022 | if (ret != 0 || !keep_cs) | |
1023 | spi_set_cs(msg->spi, false); | |
1024 | ||
1025 | if (msg->status == -EINPROGRESS) | |
1026 | msg->status = ret; | |
1027 | ||
ff61eb42 | 1028 | if (msg->status && master->handle_err) |
b716c4ff AS |
1029 | master->handle_err(master, msg); |
1030 | ||
d780c371 MS |
1031 | spi_res_release(master, msg); |
1032 | ||
b158935f MB |
1033 | spi_finalize_current_message(master); |
1034 | ||
1035 | return ret; | |
1036 | } | |
1037 | ||
1038 | /** | |
1039 | * spi_finalize_current_transfer - report completion of a transfer | |
2c675689 | 1040 | * @master: the master reporting completion |
b158935f MB |
1041 | * |
1042 | * Called by SPI drivers using the core transfer_one_message() | |
1043 | * implementation to notify it that the current interrupt driven | |
9e8f4882 | 1044 | * transfer has finished and the next one may be scheduled. |
b158935f MB |
1045 | */ |
1046 | void spi_finalize_current_transfer(struct spi_master *master) | |
1047 | { | |
1048 | complete(&master->xfer_completion); | |
1049 | } | |
1050 | EXPORT_SYMBOL_GPL(spi_finalize_current_transfer); | |
1051 | ||
ffbbdd21 | 1052 | /** |
fc9e0f71 MB |
1053 | * __spi_pump_messages - function which processes spi message queue |
1054 | * @master: master to process queue for | |
1055 | * @in_kthread: true if we are in the context of the message pump thread | |
ffbbdd21 LW |
1056 | * |
1057 | * This function checks if there is any spi message in the queue that | |
1058 | * needs processing and if so call out to the driver to initialize hardware | |
1059 | * and transfer each message. | |
1060 | * | |
0461a414 MB |
1061 | * Note that it is called both from the kthread itself and also from |
1062 | * inside spi_sync(); the queue extraction handling at the top of the | |
1063 | * function should deal with this safely. | |
ffbbdd21 | 1064 | */ |
fc9e0f71 | 1065 | static void __spi_pump_messages(struct spi_master *master, bool in_kthread) |
ffbbdd21 | 1066 | { |
ffbbdd21 LW |
1067 | unsigned long flags; |
1068 | bool was_busy = false; | |
1069 | int ret; | |
1070 | ||
983aee5d | 1071 | /* Lock queue */ |
ffbbdd21 | 1072 | spin_lock_irqsave(&master->queue_lock, flags); |
983aee5d MB |
1073 | |
1074 | /* Make sure we are not already running a message */ | |
1075 | if (master->cur_msg) { | |
1076 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1077 | return; | |
1078 | } | |
1079 | ||
0461a414 MB |
1080 | /* If another context is idling the device then defer */ |
1081 | if (master->idling) { | |
1082 | queue_kthread_work(&master->kworker, &master->pump_messages); | |
1083 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1084 | return; | |
1085 | } | |
1086 | ||
983aee5d | 1087 | /* Check if the queue is idle */ |
ffbbdd21 | 1088 | if (list_empty(&master->queue) || !master->running) { |
b0b36b86 BF |
1089 | if (!master->busy) { |
1090 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1091 | return; | |
ffbbdd21 | 1092 | } |
fc9e0f71 MB |
1093 | |
1094 | /* Only do teardown in the thread */ | |
1095 | if (!in_kthread) { | |
1096 | queue_kthread_work(&master->kworker, | |
1097 | &master->pump_messages); | |
1098 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1099 | return; | |
1100 | } | |
1101 | ||
ffbbdd21 | 1102 | master->busy = false; |
0461a414 | 1103 | master->idling = true; |
ffbbdd21 | 1104 | spin_unlock_irqrestore(&master->queue_lock, flags); |
0461a414 | 1105 | |
3a2eba9b MB |
1106 | kfree(master->dummy_rx); |
1107 | master->dummy_rx = NULL; | |
1108 | kfree(master->dummy_tx); | |
1109 | master->dummy_tx = NULL; | |
b0b36b86 BF |
1110 | if (master->unprepare_transfer_hardware && |
1111 | master->unprepare_transfer_hardware(master)) | |
1112 | dev_err(&master->dev, | |
1113 | "failed to unprepare transfer hardware\n"); | |
49834de2 MB |
1114 | if (master->auto_runtime_pm) { |
1115 | pm_runtime_mark_last_busy(master->dev.parent); | |
1116 | pm_runtime_put_autosuspend(master->dev.parent); | |
1117 | } | |
56ec1978 | 1118 | trace_spi_master_idle(master); |
ffbbdd21 | 1119 | |
0461a414 MB |
1120 | spin_lock_irqsave(&master->queue_lock, flags); |
1121 | master->idling = false; | |
ffbbdd21 LW |
1122 | spin_unlock_irqrestore(&master->queue_lock, flags); |
1123 | return; | |
1124 | } | |
ffbbdd21 | 1125 | |
ffbbdd21 LW |
1126 | /* Extract head of queue */ |
1127 | master->cur_msg = | |
a89e2d27 | 1128 | list_first_entry(&master->queue, struct spi_message, queue); |
ffbbdd21 LW |
1129 | |
1130 | list_del_init(&master->cur_msg->queue); | |
1131 | if (master->busy) | |
1132 | was_busy = true; | |
1133 | else | |
1134 | master->busy = true; | |
1135 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1136 | ||
49834de2 MB |
1137 | if (!was_busy && master->auto_runtime_pm) { |
1138 | ret = pm_runtime_get_sync(master->dev.parent); | |
1139 | if (ret < 0) { | |
1140 | dev_err(&master->dev, "Failed to power device: %d\n", | |
1141 | ret); | |
1142 | return; | |
1143 | } | |
1144 | } | |
1145 | ||
56ec1978 MB |
1146 | if (!was_busy) |
1147 | trace_spi_master_busy(master); | |
1148 | ||
7dfd2bd7 | 1149 | if (!was_busy && master->prepare_transfer_hardware) { |
ffbbdd21 LW |
1150 | ret = master->prepare_transfer_hardware(master); |
1151 | if (ret) { | |
1152 | dev_err(&master->dev, | |
1153 | "failed to prepare transfer hardware\n"); | |
49834de2 MB |
1154 | |
1155 | if (master->auto_runtime_pm) | |
1156 | pm_runtime_put(master->dev.parent); | |
ffbbdd21 LW |
1157 | return; |
1158 | } | |
1159 | } | |
1160 | ||
56ec1978 MB |
1161 | trace_spi_message_start(master->cur_msg); |
1162 | ||
2841a5fc MB |
1163 | if (master->prepare_message) { |
1164 | ret = master->prepare_message(master, master->cur_msg); | |
1165 | if (ret) { | |
1166 | dev_err(&master->dev, | |
1167 | "failed to prepare message: %d\n", ret); | |
1168 | master->cur_msg->status = ret; | |
1169 | spi_finalize_current_message(master); | |
1170 | return; | |
1171 | } | |
1172 | master->cur_msg_prepared = true; | |
1173 | } | |
1174 | ||
99adef31 MB |
1175 | ret = spi_map_msg(master, master->cur_msg); |
1176 | if (ret) { | |
1177 | master->cur_msg->status = ret; | |
1178 | spi_finalize_current_message(master); | |
1179 | return; | |
1180 | } | |
1181 | ||
ffbbdd21 LW |
1182 | ret = master->transfer_one_message(master, master->cur_msg); |
1183 | if (ret) { | |
1184 | dev_err(&master->dev, | |
1f802f82 | 1185 | "failed to transfer one message from queue\n"); |
ffbbdd21 LW |
1186 | return; |
1187 | } | |
1188 | } | |
1189 | ||
fc9e0f71 MB |
1190 | /** |
1191 | * spi_pump_messages - kthread work function which processes spi message queue | |
1192 | * @work: pointer to kthread work struct contained in the master struct | |
1193 | */ | |
1194 | static void spi_pump_messages(struct kthread_work *work) | |
1195 | { | |
1196 | struct spi_master *master = | |
1197 | container_of(work, struct spi_master, pump_messages); | |
1198 | ||
1199 | __spi_pump_messages(master, true); | |
1200 | } | |
1201 | ||
ffbbdd21 LW |
1202 | static int spi_init_queue(struct spi_master *master) |
1203 | { | |
1204 | struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 }; | |
1205 | ||
ffbbdd21 LW |
1206 | master->running = false; |
1207 | master->busy = false; | |
1208 | ||
1209 | init_kthread_worker(&master->kworker); | |
1210 | master->kworker_task = kthread_run(kthread_worker_fn, | |
f170168b | 1211 | &master->kworker, "%s", |
ffbbdd21 LW |
1212 | dev_name(&master->dev)); |
1213 | if (IS_ERR(master->kworker_task)) { | |
1214 | dev_err(&master->dev, "failed to create message pump task\n"); | |
98a8f5a0 | 1215 | return PTR_ERR(master->kworker_task); |
ffbbdd21 LW |
1216 | } |
1217 | init_kthread_work(&master->pump_messages, spi_pump_messages); | |
1218 | ||
1219 | /* | |
1220 | * Master config will indicate if this controller should run the | |
1221 | * message pump with high (realtime) priority to reduce the transfer | |
1222 | * latency on the bus by minimising the delay between a transfer | |
1223 | * request and the scheduling of the message pump thread. Without this | |
1224 | * setting the message pump thread will remain at default priority. | |
1225 | */ | |
1226 | if (master->rt) { | |
1227 | dev_info(&master->dev, | |
1228 | "will run message pump with realtime priority\n"); | |
1229 | sched_setscheduler(master->kworker_task, SCHED_FIFO, ¶m); | |
1230 | } | |
1231 | ||
1232 | return 0; | |
1233 | } | |
1234 | ||
1235 | /** | |
1236 | * spi_get_next_queued_message() - called by driver to check for queued | |
1237 | * messages | |
1238 | * @master: the master to check for queued messages | |
1239 | * | |
1240 | * If there are more messages in the queue, the next message is returned from | |
1241 | * this call. | |
97d56dc6 JMC |
1242 | * |
1243 | * Return: the next message in the queue, else NULL if the queue is empty. | |
ffbbdd21 LW |
1244 | */ |
1245 | struct spi_message *spi_get_next_queued_message(struct spi_master *master) | |
1246 | { | |
1247 | struct spi_message *next; | |
1248 | unsigned long flags; | |
1249 | ||
1250 | /* get a pointer to the next message, if any */ | |
1251 | spin_lock_irqsave(&master->queue_lock, flags); | |
1cfd97f9 AL |
1252 | next = list_first_entry_or_null(&master->queue, struct spi_message, |
1253 | queue); | |
ffbbdd21 LW |
1254 | spin_unlock_irqrestore(&master->queue_lock, flags); |
1255 | ||
1256 | return next; | |
1257 | } | |
1258 | EXPORT_SYMBOL_GPL(spi_get_next_queued_message); | |
1259 | ||
1260 | /** | |
1261 | * spi_finalize_current_message() - the current message is complete | |
1262 | * @master: the master to return the message to | |
1263 | * | |
1264 | * Called by the driver to notify the core that the message in the front of the | |
1265 | * queue is complete and can be removed from the queue. | |
1266 | */ | |
1267 | void spi_finalize_current_message(struct spi_master *master) | |
1268 | { | |
1269 | struct spi_message *mesg; | |
1270 | unsigned long flags; | |
2841a5fc | 1271 | int ret; |
ffbbdd21 LW |
1272 | |
1273 | spin_lock_irqsave(&master->queue_lock, flags); | |
1274 | mesg = master->cur_msg; | |
ffbbdd21 LW |
1275 | spin_unlock_irqrestore(&master->queue_lock, flags); |
1276 | ||
99adef31 MB |
1277 | spi_unmap_msg(master, mesg); |
1278 | ||
2841a5fc MB |
1279 | if (master->cur_msg_prepared && master->unprepare_message) { |
1280 | ret = master->unprepare_message(master, mesg); | |
1281 | if (ret) { | |
1282 | dev_err(&master->dev, | |
1283 | "failed to unprepare message: %d\n", ret); | |
1284 | } | |
1285 | } | |
391949b6 | 1286 | |
8e76ef88 MS |
1287 | spin_lock_irqsave(&master->queue_lock, flags); |
1288 | master->cur_msg = NULL; | |
2841a5fc | 1289 | master->cur_msg_prepared = false; |
8e76ef88 MS |
1290 | queue_kthread_work(&master->kworker, &master->pump_messages); |
1291 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1292 | ||
1293 | trace_spi_message_done(mesg); | |
2841a5fc | 1294 | |
ffbbdd21 LW |
1295 | mesg->state = NULL; |
1296 | if (mesg->complete) | |
1297 | mesg->complete(mesg->context); | |
1298 | } | |
1299 | EXPORT_SYMBOL_GPL(spi_finalize_current_message); | |
1300 | ||
1301 | static int spi_start_queue(struct spi_master *master) | |
1302 | { | |
1303 | unsigned long flags; | |
1304 | ||
1305 | spin_lock_irqsave(&master->queue_lock, flags); | |
1306 | ||
1307 | if (master->running || master->busy) { | |
1308 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1309 | return -EBUSY; | |
1310 | } | |
1311 | ||
1312 | master->running = true; | |
1313 | master->cur_msg = NULL; | |
1314 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1315 | ||
1316 | queue_kthread_work(&master->kworker, &master->pump_messages); | |
1317 | ||
1318 | return 0; | |
1319 | } | |
1320 | ||
1321 | static int spi_stop_queue(struct spi_master *master) | |
1322 | { | |
1323 | unsigned long flags; | |
1324 | unsigned limit = 500; | |
1325 | int ret = 0; | |
1326 | ||
1327 | spin_lock_irqsave(&master->queue_lock, flags); | |
1328 | ||
1329 | /* | |
1330 | * This is a bit lame, but is optimized for the common execution path. | |
1331 | * A wait_queue on the master->busy could be used, but then the common | |
1332 | * execution path (pump_messages) would be required to call wake_up or | |
1333 | * friends on every SPI message. Do this instead. | |
1334 | */ | |
1335 | while ((!list_empty(&master->queue) || master->busy) && limit--) { | |
1336 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
f97b26b0 | 1337 | usleep_range(10000, 11000); |
ffbbdd21 LW |
1338 | spin_lock_irqsave(&master->queue_lock, flags); |
1339 | } | |
1340 | ||
1341 | if (!list_empty(&master->queue) || master->busy) | |
1342 | ret = -EBUSY; | |
1343 | else | |
1344 | master->running = false; | |
1345 | ||
1346 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1347 | ||
1348 | if (ret) { | |
1349 | dev_warn(&master->dev, | |
1350 | "could not stop message queue\n"); | |
1351 | return ret; | |
1352 | } | |
1353 | return ret; | |
1354 | } | |
1355 | ||
1356 | static int spi_destroy_queue(struct spi_master *master) | |
1357 | { | |
1358 | int ret; | |
1359 | ||
1360 | ret = spi_stop_queue(master); | |
1361 | ||
1362 | /* | |
1363 | * flush_kthread_worker will block until all work is done. | |
1364 | * If the reason that stop_queue timed out is that the work will never | |
1365 | * finish, then it does no good to call flush/stop thread, so | |
1366 | * return anyway. | |
1367 | */ | |
1368 | if (ret) { | |
1369 | dev_err(&master->dev, "problem destroying queue\n"); | |
1370 | return ret; | |
1371 | } | |
1372 | ||
1373 | flush_kthread_worker(&master->kworker); | |
1374 | kthread_stop(master->kworker_task); | |
1375 | ||
1376 | return 0; | |
1377 | } | |
1378 | ||
0461a414 MB |
1379 | static int __spi_queued_transfer(struct spi_device *spi, |
1380 | struct spi_message *msg, | |
1381 | bool need_pump) | |
ffbbdd21 LW |
1382 | { |
1383 | struct spi_master *master = spi->master; | |
1384 | unsigned long flags; | |
1385 | ||
1386 | spin_lock_irqsave(&master->queue_lock, flags); | |
1387 | ||
1388 | if (!master->running) { | |
1389 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1390 | return -ESHUTDOWN; | |
1391 | } | |
1392 | msg->actual_length = 0; | |
1393 | msg->status = -EINPROGRESS; | |
1394 | ||
1395 | list_add_tail(&msg->queue, &master->queue); | |
0461a414 | 1396 | if (!master->busy && need_pump) |
ffbbdd21 LW |
1397 | queue_kthread_work(&master->kworker, &master->pump_messages); |
1398 | ||
1399 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1400 | return 0; | |
1401 | } | |
1402 | ||
0461a414 MB |
1403 | /** |
1404 | * spi_queued_transfer - transfer function for queued transfers | |
1405 | * @spi: spi device which is requesting transfer | |
1406 | * @msg: spi message which is to handled is queued to driver queue | |
97d56dc6 JMC |
1407 | * |
1408 | * Return: zero on success, else a negative error code. | |
0461a414 MB |
1409 | */ |
1410 | static int spi_queued_transfer(struct spi_device *spi, struct spi_message *msg) | |
1411 | { | |
1412 | return __spi_queued_transfer(spi, msg, true); | |
1413 | } | |
1414 | ||
ffbbdd21 LW |
1415 | static int spi_master_initialize_queue(struct spi_master *master) |
1416 | { | |
1417 | int ret; | |
1418 | ||
ffbbdd21 | 1419 | master->transfer = spi_queued_transfer; |
b158935f MB |
1420 | if (!master->transfer_one_message) |
1421 | master->transfer_one_message = spi_transfer_one_message; | |
ffbbdd21 LW |
1422 | |
1423 | /* Initialize and start queue */ | |
1424 | ret = spi_init_queue(master); | |
1425 | if (ret) { | |
1426 | dev_err(&master->dev, "problem initializing queue\n"); | |
1427 | goto err_init_queue; | |
1428 | } | |
c3676d5c | 1429 | master->queued = true; |
ffbbdd21 LW |
1430 | ret = spi_start_queue(master); |
1431 | if (ret) { | |
1432 | dev_err(&master->dev, "problem starting queue\n"); | |
1433 | goto err_start_queue; | |
1434 | } | |
1435 | ||
1436 | return 0; | |
1437 | ||
1438 | err_start_queue: | |
ffbbdd21 | 1439 | spi_destroy_queue(master); |
c3676d5c | 1440 | err_init_queue: |
ffbbdd21 LW |
1441 | return ret; |
1442 | } | |
1443 | ||
1444 | /*-------------------------------------------------------------------------*/ | |
1445 | ||
7cb94361 | 1446 | #if defined(CONFIG_OF) |
aff5e3f8 PA |
1447 | static struct spi_device * |
1448 | of_register_spi_device(struct spi_master *master, struct device_node *nc) | |
1449 | { | |
1450 | struct spi_device *spi; | |
1451 | int rc; | |
1452 | u32 value; | |
1453 | ||
1454 | /* Alloc an spi_device */ | |
1455 | spi = spi_alloc_device(master); | |
1456 | if (!spi) { | |
1457 | dev_err(&master->dev, "spi_device alloc error for %s\n", | |
1458 | nc->full_name); | |
1459 | rc = -ENOMEM; | |
1460 | goto err_out; | |
1461 | } | |
1462 | ||
1463 | /* Select device driver */ | |
1464 | rc = of_modalias_node(nc, spi->modalias, | |
1465 | sizeof(spi->modalias)); | |
1466 | if (rc < 0) { | |
1467 | dev_err(&master->dev, "cannot find modalias for %s\n", | |
1468 | nc->full_name); | |
1469 | goto err_out; | |
1470 | } | |
1471 | ||
1472 | /* Device address */ | |
1473 | rc = of_property_read_u32(nc, "reg", &value); | |
1474 | if (rc) { | |
1475 | dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n", | |
1476 | nc->full_name, rc); | |
1477 | goto err_out; | |
1478 | } | |
1479 | spi->chip_select = value; | |
1480 | ||
1481 | /* Mode (clock phase/polarity/etc.) */ | |
1482 | if (of_find_property(nc, "spi-cpha", NULL)) | |
1483 | spi->mode |= SPI_CPHA; | |
1484 | if (of_find_property(nc, "spi-cpol", NULL)) | |
1485 | spi->mode |= SPI_CPOL; | |
1486 | if (of_find_property(nc, "spi-cs-high", NULL)) | |
1487 | spi->mode |= SPI_CS_HIGH; | |
1488 | if (of_find_property(nc, "spi-3wire", NULL)) | |
1489 | spi->mode |= SPI_3WIRE; | |
1490 | if (of_find_property(nc, "spi-lsb-first", NULL)) | |
1491 | spi->mode |= SPI_LSB_FIRST; | |
1492 | ||
1493 | /* Device DUAL/QUAD mode */ | |
1494 | if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) { | |
1495 | switch (value) { | |
1496 | case 1: | |
1497 | break; | |
1498 | case 2: | |
1499 | spi->mode |= SPI_TX_DUAL; | |
1500 | break; | |
1501 | case 4: | |
1502 | spi->mode |= SPI_TX_QUAD; | |
1503 | break; | |
1504 | default: | |
1505 | dev_warn(&master->dev, | |
1506 | "spi-tx-bus-width %d not supported\n", | |
1507 | value); | |
1508 | break; | |
1509 | } | |
1510 | } | |
1511 | ||
1512 | if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) { | |
1513 | switch (value) { | |
1514 | case 1: | |
1515 | break; | |
1516 | case 2: | |
1517 | spi->mode |= SPI_RX_DUAL; | |
1518 | break; | |
1519 | case 4: | |
1520 | spi->mode |= SPI_RX_QUAD; | |
1521 | break; | |
1522 | default: | |
1523 | dev_warn(&master->dev, | |
1524 | "spi-rx-bus-width %d not supported\n", | |
1525 | value); | |
1526 | break; | |
1527 | } | |
1528 | } | |
1529 | ||
1530 | /* Device speed */ | |
1531 | rc = of_property_read_u32(nc, "spi-max-frequency", &value); | |
1532 | if (rc) { | |
1533 | dev_err(&master->dev, "%s has no valid 'spi-max-frequency' property (%d)\n", | |
1534 | nc->full_name, rc); | |
1535 | goto err_out; | |
1536 | } | |
1537 | spi->max_speed_hz = value; | |
1538 | ||
aff5e3f8 PA |
1539 | /* Store a pointer to the node in the device structure */ |
1540 | of_node_get(nc); | |
1541 | spi->dev.of_node = nc; | |
1542 | ||
1543 | /* Register the new device */ | |
aff5e3f8 PA |
1544 | rc = spi_add_device(spi); |
1545 | if (rc) { | |
1546 | dev_err(&master->dev, "spi_device register error %s\n", | |
1547 | nc->full_name); | |
1548 | goto err_out; | |
1549 | } | |
1550 | ||
1551 | return spi; | |
1552 | ||
1553 | err_out: | |
1554 | spi_dev_put(spi); | |
1555 | return ERR_PTR(rc); | |
1556 | } | |
1557 | ||
d57a4282 GL |
1558 | /** |
1559 | * of_register_spi_devices() - Register child devices onto the SPI bus | |
1560 | * @master: Pointer to spi_master device | |
1561 | * | |
1562 | * Registers an spi_device for each child node of master node which has a 'reg' | |
1563 | * property. | |
1564 | */ | |
1565 | static void of_register_spi_devices(struct spi_master *master) | |
1566 | { | |
1567 | struct spi_device *spi; | |
1568 | struct device_node *nc; | |
d57a4282 GL |
1569 | |
1570 | if (!master->dev.of_node) | |
1571 | return; | |
1572 | ||
f3b6159e | 1573 | for_each_available_child_of_node(master->dev.of_node, nc) { |
bd6c1644 GU |
1574 | if (of_node_test_and_set_flag(nc, OF_POPULATED)) |
1575 | continue; | |
aff5e3f8 PA |
1576 | spi = of_register_spi_device(master, nc); |
1577 | if (IS_ERR(spi)) | |
1578 | dev_warn(&master->dev, "Failed to create SPI device for %s\n", | |
d57a4282 | 1579 | nc->full_name); |
d57a4282 GL |
1580 | } |
1581 | } | |
1582 | #else | |
1583 | static void of_register_spi_devices(struct spi_master *master) { } | |
1584 | #endif | |
1585 | ||
64bee4d2 MW |
1586 | #ifdef CONFIG_ACPI |
1587 | static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) | |
1588 | { | |
1589 | struct spi_device *spi = data; | |
1590 | ||
1591 | if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) { | |
1592 | struct acpi_resource_spi_serialbus *sb; | |
1593 | ||
1594 | sb = &ares->data.spi_serial_bus; | |
1595 | if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_SPI) { | |
1596 | spi->chip_select = sb->device_selection; | |
1597 | spi->max_speed_hz = sb->connection_speed; | |
1598 | ||
1599 | if (sb->clock_phase == ACPI_SPI_SECOND_PHASE) | |
1600 | spi->mode |= SPI_CPHA; | |
1601 | if (sb->clock_polarity == ACPI_SPI_START_HIGH) | |
1602 | spi->mode |= SPI_CPOL; | |
1603 | if (sb->device_polarity == ACPI_SPI_ACTIVE_HIGH) | |
1604 | spi->mode |= SPI_CS_HIGH; | |
1605 | } | |
1606 | } else if (spi->irq < 0) { | |
1607 | struct resource r; | |
1608 | ||
1609 | if (acpi_dev_resource_interrupt(ares, 0, &r)) | |
1610 | spi->irq = r.start; | |
1611 | } | |
1612 | ||
1613 | /* Always tell the ACPI core to skip this resource */ | |
1614 | return 1; | |
1615 | } | |
1616 | ||
1617 | static acpi_status acpi_spi_add_device(acpi_handle handle, u32 level, | |
1618 | void *data, void **return_value) | |
1619 | { | |
1620 | struct spi_master *master = data; | |
1621 | struct list_head resource_list; | |
1622 | struct acpi_device *adev; | |
1623 | struct spi_device *spi; | |
1624 | int ret; | |
1625 | ||
1626 | if (acpi_bus_get_device(handle, &adev)) | |
1627 | return AE_OK; | |
1628 | if (acpi_bus_get_status(adev) || !adev->status.present) | |
1629 | return AE_OK; | |
1630 | ||
1631 | spi = spi_alloc_device(master); | |
1632 | if (!spi) { | |
1633 | dev_err(&master->dev, "failed to allocate SPI device for %s\n", | |
1634 | dev_name(&adev->dev)); | |
1635 | return AE_NO_MEMORY; | |
1636 | } | |
1637 | ||
7b199811 | 1638 | ACPI_COMPANION_SET(&spi->dev, adev); |
64bee4d2 MW |
1639 | spi->irq = -1; |
1640 | ||
1641 | INIT_LIST_HEAD(&resource_list); | |
1642 | ret = acpi_dev_get_resources(adev, &resource_list, | |
1643 | acpi_spi_add_resource, spi); | |
1644 | acpi_dev_free_resource_list(&resource_list); | |
1645 | ||
1646 | if (ret < 0 || !spi->max_speed_hz) { | |
1647 | spi_dev_put(spi); | |
1648 | return AE_OK; | |
1649 | } | |
1650 | ||
33ada67d CR |
1651 | if (spi->irq < 0) |
1652 | spi->irq = acpi_dev_gpio_irq_get(adev, 0); | |
1653 | ||
33cf00e5 | 1654 | adev->power.flags.ignore_parent = true; |
cf9eb39c | 1655 | strlcpy(spi->modalias, acpi_device_hid(adev), sizeof(spi->modalias)); |
64bee4d2 | 1656 | if (spi_add_device(spi)) { |
33cf00e5 | 1657 | adev->power.flags.ignore_parent = false; |
64bee4d2 MW |
1658 | dev_err(&master->dev, "failed to add SPI device %s from ACPI\n", |
1659 | dev_name(&adev->dev)); | |
1660 | spi_dev_put(spi); | |
1661 | } | |
1662 | ||
1663 | return AE_OK; | |
1664 | } | |
1665 | ||
1666 | static void acpi_register_spi_devices(struct spi_master *master) | |
1667 | { | |
1668 | acpi_status status; | |
1669 | acpi_handle handle; | |
1670 | ||
29896178 | 1671 | handle = ACPI_HANDLE(master->dev.parent); |
64bee4d2 MW |
1672 | if (!handle) |
1673 | return; | |
1674 | ||
1675 | status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, | |
1676 | acpi_spi_add_device, NULL, | |
1677 | master, NULL); | |
1678 | if (ACPI_FAILURE(status)) | |
1679 | dev_warn(&master->dev, "failed to enumerate SPI slaves\n"); | |
1680 | } | |
1681 | #else | |
1682 | static inline void acpi_register_spi_devices(struct spi_master *master) {} | |
1683 | #endif /* CONFIG_ACPI */ | |
1684 | ||
49dce689 | 1685 | static void spi_master_release(struct device *dev) |
8ae12a0d DB |
1686 | { |
1687 | struct spi_master *master; | |
1688 | ||
49dce689 | 1689 | master = container_of(dev, struct spi_master, dev); |
8ae12a0d DB |
1690 | kfree(master); |
1691 | } | |
1692 | ||
1693 | static struct class spi_master_class = { | |
1694 | .name = "spi_master", | |
1695 | .owner = THIS_MODULE, | |
49dce689 | 1696 | .dev_release = spi_master_release, |
eca2ebc7 | 1697 | .dev_groups = spi_master_groups, |
8ae12a0d DB |
1698 | }; |
1699 | ||
1700 | ||
1701 | /** | |
1702 | * spi_alloc_master - allocate SPI master controller | |
1703 | * @dev: the controller, possibly using the platform_bus | |
33e34dc6 | 1704 | * @size: how much zeroed driver-private data to allocate; the pointer to this |
49dce689 | 1705 | * memory is in the driver_data field of the returned device, |
0c868461 | 1706 | * accessible with spi_master_get_devdata(). |
33e34dc6 | 1707 | * Context: can sleep |
8ae12a0d DB |
1708 | * |
1709 | * This call is used only by SPI master controller drivers, which are the | |
1710 | * only ones directly touching chip registers. It's how they allocate | |
ba1a0513 | 1711 | * an spi_master structure, prior to calling spi_register_master(). |
8ae12a0d | 1712 | * |
97d56dc6 | 1713 | * This must be called from context that can sleep. |
8ae12a0d DB |
1714 | * |
1715 | * The caller is responsible for assigning the bus number and initializing | |
ba1a0513 | 1716 | * the master's methods before calling spi_register_master(); and (after errors |
a394d635 | 1717 | * adding the device) calling spi_master_put() to prevent a memory leak. |
97d56dc6 JMC |
1718 | * |
1719 | * Return: the SPI master structure on success, else NULL. | |
8ae12a0d | 1720 | */ |
e9d5a461 | 1721 | struct spi_master *spi_alloc_master(struct device *dev, unsigned size) |
8ae12a0d DB |
1722 | { |
1723 | struct spi_master *master; | |
1724 | ||
0c868461 DB |
1725 | if (!dev) |
1726 | return NULL; | |
1727 | ||
5fe5f05e | 1728 | master = kzalloc(size + sizeof(*master), GFP_KERNEL); |
8ae12a0d DB |
1729 | if (!master) |
1730 | return NULL; | |
1731 | ||
49dce689 | 1732 | device_initialize(&master->dev); |
1e8a52e1 GL |
1733 | master->bus_num = -1; |
1734 | master->num_chipselect = 1; | |
49dce689 | 1735 | master->dev.class = &spi_master_class; |
157f38f9 | 1736 | master->dev.parent = dev; |
0c868461 | 1737 | spi_master_set_devdata(master, &master[1]); |
8ae12a0d DB |
1738 | |
1739 | return master; | |
1740 | } | |
1741 | EXPORT_SYMBOL_GPL(spi_alloc_master); | |
1742 | ||
74317984 JCPV |
1743 | #ifdef CONFIG_OF |
1744 | static int of_spi_register_master(struct spi_master *master) | |
1745 | { | |
e80beb27 | 1746 | int nb, i, *cs; |
74317984 JCPV |
1747 | struct device_node *np = master->dev.of_node; |
1748 | ||
1749 | if (!np) | |
1750 | return 0; | |
1751 | ||
1752 | nb = of_gpio_named_count(np, "cs-gpios"); | |
5fe5f05e | 1753 | master->num_chipselect = max_t(int, nb, master->num_chipselect); |
74317984 | 1754 | |
8ec5d84e AL |
1755 | /* Return error only for an incorrectly formed cs-gpios property */ |
1756 | if (nb == 0 || nb == -ENOENT) | |
74317984 | 1757 | return 0; |
8ec5d84e AL |
1758 | else if (nb < 0) |
1759 | return nb; | |
74317984 JCPV |
1760 | |
1761 | cs = devm_kzalloc(&master->dev, | |
1762 | sizeof(int) * master->num_chipselect, | |
1763 | GFP_KERNEL); | |
1764 | master->cs_gpios = cs; | |
1765 | ||
1766 | if (!master->cs_gpios) | |
1767 | return -ENOMEM; | |
1768 | ||
0da83bb1 | 1769 | for (i = 0; i < master->num_chipselect; i++) |
446411e1 | 1770 | cs[i] = -ENOENT; |
74317984 JCPV |
1771 | |
1772 | for (i = 0; i < nb; i++) | |
1773 | cs[i] = of_get_named_gpio(np, "cs-gpios", i); | |
1774 | ||
1775 | return 0; | |
1776 | } | |
1777 | #else | |
1778 | static int of_spi_register_master(struct spi_master *master) | |
1779 | { | |
1780 | return 0; | |
1781 | } | |
1782 | #endif | |
1783 | ||
8ae12a0d DB |
1784 | /** |
1785 | * spi_register_master - register SPI master controller | |
1786 | * @master: initialized master, originally from spi_alloc_master() | |
33e34dc6 | 1787 | * Context: can sleep |
8ae12a0d DB |
1788 | * |
1789 | * SPI master controllers connect to their drivers using some non-SPI bus, | |
1790 | * such as the platform bus. The final stage of probe() in that code | |
1791 | * includes calling spi_register_master() to hook up to this SPI bus glue. | |
1792 | * | |
1793 | * SPI controllers use board specific (often SOC specific) bus numbers, | |
1794 | * and board-specific addressing for SPI devices combines those numbers | |
1795 | * with chip select numbers. Since SPI does not directly support dynamic | |
1796 | * device identification, boards need configuration tables telling which | |
1797 | * chip is at which address. | |
1798 | * | |
1799 | * This must be called from context that can sleep. It returns zero on | |
1800 | * success, else a negative error code (dropping the master's refcount). | |
0c868461 DB |
1801 | * After a successful return, the caller is responsible for calling |
1802 | * spi_unregister_master(). | |
97d56dc6 JMC |
1803 | * |
1804 | * Return: zero on success, else a negative error code. | |
8ae12a0d | 1805 | */ |
e9d5a461 | 1806 | int spi_register_master(struct spi_master *master) |
8ae12a0d | 1807 | { |
e44a45ae | 1808 | static atomic_t dyn_bus_id = ATOMIC_INIT((1<<15) - 1); |
49dce689 | 1809 | struct device *dev = master->dev.parent; |
2b9603a0 | 1810 | struct boardinfo *bi; |
8ae12a0d DB |
1811 | int status = -ENODEV; |
1812 | int dynamic = 0; | |
1813 | ||
0c868461 DB |
1814 | if (!dev) |
1815 | return -ENODEV; | |
1816 | ||
74317984 JCPV |
1817 | status = of_spi_register_master(master); |
1818 | if (status) | |
1819 | return status; | |
1820 | ||
082c8cb4 DB |
1821 | /* even if it's just one always-selected device, there must |
1822 | * be at least one chipselect | |
1823 | */ | |
1824 | if (master->num_chipselect == 0) | |
1825 | return -EINVAL; | |
1826 | ||
bb29785e GL |
1827 | if ((master->bus_num < 0) && master->dev.of_node) |
1828 | master->bus_num = of_alias_get_id(master->dev.of_node, "spi"); | |
1829 | ||
8ae12a0d | 1830 | /* convention: dynamically assigned bus IDs count down from the max */ |
a020ed75 | 1831 | if (master->bus_num < 0) { |
082c8cb4 DB |
1832 | /* FIXME switch to an IDR based scheme, something like |
1833 | * I2C now uses, so we can't run out of "dynamic" IDs | |
1834 | */ | |
8ae12a0d | 1835 | master->bus_num = atomic_dec_return(&dyn_bus_id); |
b885244e | 1836 | dynamic = 1; |
8ae12a0d DB |
1837 | } |
1838 | ||
5424d43e MB |
1839 | INIT_LIST_HEAD(&master->queue); |
1840 | spin_lock_init(&master->queue_lock); | |
cf32b71e ES |
1841 | spin_lock_init(&master->bus_lock_spinlock); |
1842 | mutex_init(&master->bus_lock_mutex); | |
1843 | master->bus_lock_flag = 0; | |
b158935f | 1844 | init_completion(&master->xfer_completion); |
6ad45a27 MB |
1845 | if (!master->max_dma_len) |
1846 | master->max_dma_len = INT_MAX; | |
cf32b71e | 1847 | |
8ae12a0d DB |
1848 | /* register the device, then userspace will see it. |
1849 | * registration fails if the bus ID is in use. | |
1850 | */ | |
35f74fca | 1851 | dev_set_name(&master->dev, "spi%u", master->bus_num); |
49dce689 | 1852 | status = device_add(&master->dev); |
b885244e | 1853 | if (status < 0) |
8ae12a0d | 1854 | goto done; |
35f74fca | 1855 | dev_dbg(dev, "registered master %s%s\n", dev_name(&master->dev), |
8ae12a0d DB |
1856 | dynamic ? " (dynamic)" : ""); |
1857 | ||
ffbbdd21 LW |
1858 | /* If we're using a queued driver, start the queue */ |
1859 | if (master->transfer) | |
1860 | dev_info(dev, "master is unqueued, this is deprecated\n"); | |
1861 | else { | |
1862 | status = spi_master_initialize_queue(master); | |
1863 | if (status) { | |
e93b0724 | 1864 | device_del(&master->dev); |
ffbbdd21 LW |
1865 | goto done; |
1866 | } | |
1867 | } | |
eca2ebc7 MS |
1868 | /* add statistics */ |
1869 | spin_lock_init(&master->statistics.lock); | |
ffbbdd21 | 1870 | |
2b9603a0 FT |
1871 | mutex_lock(&board_lock); |
1872 | list_add_tail(&master->list, &spi_master_list); | |
1873 | list_for_each_entry(bi, &board_list, list) | |
1874 | spi_match_master_to_boardinfo(master, &bi->board_info); | |
1875 | mutex_unlock(&board_lock); | |
1876 | ||
64bee4d2 | 1877 | /* Register devices from the device tree and ACPI */ |
12b15e83 | 1878 | of_register_spi_devices(master); |
64bee4d2 | 1879 | acpi_register_spi_devices(master); |
8ae12a0d DB |
1880 | done: |
1881 | return status; | |
1882 | } | |
1883 | EXPORT_SYMBOL_GPL(spi_register_master); | |
1884 | ||
666d5b4c MB |
1885 | static void devm_spi_unregister(struct device *dev, void *res) |
1886 | { | |
1887 | spi_unregister_master(*(struct spi_master **)res); | |
1888 | } | |
1889 | ||
1890 | /** | |
1891 | * dev_spi_register_master - register managed SPI master controller | |
1892 | * @dev: device managing SPI master | |
1893 | * @master: initialized master, originally from spi_alloc_master() | |
1894 | * Context: can sleep | |
1895 | * | |
1896 | * Register a SPI device as with spi_register_master() which will | |
1897 | * automatically be unregister | |
97d56dc6 JMC |
1898 | * |
1899 | * Return: zero on success, else a negative error code. | |
666d5b4c MB |
1900 | */ |
1901 | int devm_spi_register_master(struct device *dev, struct spi_master *master) | |
1902 | { | |
1903 | struct spi_master **ptr; | |
1904 | int ret; | |
1905 | ||
1906 | ptr = devres_alloc(devm_spi_unregister, sizeof(*ptr), GFP_KERNEL); | |
1907 | if (!ptr) | |
1908 | return -ENOMEM; | |
1909 | ||
1910 | ret = spi_register_master(master); | |
4b92894e | 1911 | if (!ret) { |
666d5b4c MB |
1912 | *ptr = master; |
1913 | devres_add(dev, ptr); | |
1914 | } else { | |
1915 | devres_free(ptr); | |
1916 | } | |
1917 | ||
1918 | return ret; | |
1919 | } | |
1920 | EXPORT_SYMBOL_GPL(devm_spi_register_master); | |
1921 | ||
34860089 | 1922 | static int __unregister(struct device *dev, void *null) |
8ae12a0d | 1923 | { |
34860089 | 1924 | spi_unregister_device(to_spi_device(dev)); |
8ae12a0d DB |
1925 | return 0; |
1926 | } | |
1927 | ||
1928 | /** | |
1929 | * spi_unregister_master - unregister SPI master controller | |
1930 | * @master: the master being unregistered | |
33e34dc6 | 1931 | * Context: can sleep |
8ae12a0d DB |
1932 | * |
1933 | * This call is used only by SPI master controller drivers, which are the | |
1934 | * only ones directly touching chip registers. | |
1935 | * | |
1936 | * This must be called from context that can sleep. | |
1937 | */ | |
1938 | void spi_unregister_master(struct spi_master *master) | |
1939 | { | |
89fc9a1a JG |
1940 | int dummy; |
1941 | ||
ffbbdd21 LW |
1942 | if (master->queued) { |
1943 | if (spi_destroy_queue(master)) | |
1944 | dev_err(&master->dev, "queue remove failed\n"); | |
1945 | } | |
1946 | ||
2b9603a0 FT |
1947 | mutex_lock(&board_lock); |
1948 | list_del(&master->list); | |
1949 | mutex_unlock(&board_lock); | |
1950 | ||
97dbf37d | 1951 | dummy = device_for_each_child(&master->dev, NULL, __unregister); |
49dce689 | 1952 | device_unregister(&master->dev); |
8ae12a0d DB |
1953 | } |
1954 | EXPORT_SYMBOL_GPL(spi_unregister_master); | |
1955 | ||
ffbbdd21 LW |
1956 | int spi_master_suspend(struct spi_master *master) |
1957 | { | |
1958 | int ret; | |
1959 | ||
1960 | /* Basically no-ops for non-queued masters */ | |
1961 | if (!master->queued) | |
1962 | return 0; | |
1963 | ||
1964 | ret = spi_stop_queue(master); | |
1965 | if (ret) | |
1966 | dev_err(&master->dev, "queue stop failed\n"); | |
1967 | ||
1968 | return ret; | |
1969 | } | |
1970 | EXPORT_SYMBOL_GPL(spi_master_suspend); | |
1971 | ||
1972 | int spi_master_resume(struct spi_master *master) | |
1973 | { | |
1974 | int ret; | |
1975 | ||
1976 | if (!master->queued) | |
1977 | return 0; | |
1978 | ||
1979 | ret = spi_start_queue(master); | |
1980 | if (ret) | |
1981 | dev_err(&master->dev, "queue restart failed\n"); | |
1982 | ||
1983 | return ret; | |
1984 | } | |
1985 | EXPORT_SYMBOL_GPL(spi_master_resume); | |
1986 | ||
9f3b795a | 1987 | static int __spi_master_match(struct device *dev, const void *data) |
5ed2c832 DY |
1988 | { |
1989 | struct spi_master *m; | |
9f3b795a | 1990 | const u16 *bus_num = data; |
5ed2c832 DY |
1991 | |
1992 | m = container_of(dev, struct spi_master, dev); | |
1993 | return m->bus_num == *bus_num; | |
1994 | } | |
1995 | ||
8ae12a0d DB |
1996 | /** |
1997 | * spi_busnum_to_master - look up master associated with bus_num | |
1998 | * @bus_num: the master's bus number | |
33e34dc6 | 1999 | * Context: can sleep |
8ae12a0d DB |
2000 | * |
2001 | * This call may be used with devices that are registered after | |
2002 | * arch init time. It returns a refcounted pointer to the relevant | |
2003 | * spi_master (which the caller must release), or NULL if there is | |
2004 | * no such master registered. | |
97d56dc6 JMC |
2005 | * |
2006 | * Return: the SPI master structure on success, else NULL. | |
8ae12a0d DB |
2007 | */ |
2008 | struct spi_master *spi_busnum_to_master(u16 bus_num) | |
2009 | { | |
49dce689 | 2010 | struct device *dev; |
1e9a51dc | 2011 | struct spi_master *master = NULL; |
5ed2c832 | 2012 | |
695794ae | 2013 | dev = class_find_device(&spi_master_class, NULL, &bus_num, |
5ed2c832 DY |
2014 | __spi_master_match); |
2015 | if (dev) | |
2016 | master = container_of(dev, struct spi_master, dev); | |
2017 | /* reference got in class_find_device */ | |
1e9a51dc | 2018 | return master; |
8ae12a0d DB |
2019 | } |
2020 | EXPORT_SYMBOL_GPL(spi_busnum_to_master); | |
2021 | ||
d780c371 MS |
2022 | /*-------------------------------------------------------------------------*/ |
2023 | ||
2024 | /* Core methods for SPI resource management */ | |
2025 | ||
2026 | /** | |
2027 | * spi_res_alloc - allocate a spi resource that is life-cycle managed | |
2028 | * during the processing of a spi_message while using | |
2029 | * spi_transfer_one | |
2030 | * @spi: the spi device for which we allocate memory | |
2031 | * @release: the release code to execute for this resource | |
2032 | * @size: size to alloc and return | |
2033 | * @gfp: GFP allocation flags | |
2034 | * | |
2035 | * Return: the pointer to the allocated data | |
2036 | * | |
2037 | * This may get enhanced in the future to allocate from a memory pool | |
2038 | * of the @spi_device or @spi_master to avoid repeated allocations. | |
2039 | */ | |
2040 | void *spi_res_alloc(struct spi_device *spi, | |
2041 | spi_res_release_t release, | |
2042 | size_t size, gfp_t gfp) | |
2043 | { | |
2044 | struct spi_res *sres; | |
2045 | ||
2046 | sres = kzalloc(sizeof(*sres) + size, gfp); | |
2047 | if (!sres) | |
2048 | return NULL; | |
2049 | ||
2050 | INIT_LIST_HEAD(&sres->entry); | |
2051 | sres->release = release; | |
2052 | ||
2053 | return sres->data; | |
2054 | } | |
2055 | EXPORT_SYMBOL_GPL(spi_res_alloc); | |
2056 | ||
2057 | /** | |
2058 | * spi_res_free - free an spi resource | |
2059 | * @res: pointer to the custom data of a resource | |
2060 | * | |
2061 | */ | |
2062 | void spi_res_free(void *res) | |
2063 | { | |
2064 | struct spi_res *sres = container_of(res, struct spi_res, data); | |
2065 | ||
2066 | if (!res) | |
2067 | return; | |
2068 | ||
2069 | WARN_ON(!list_empty(&sres->entry)); | |
2070 | kfree(sres); | |
2071 | } | |
2072 | EXPORT_SYMBOL_GPL(spi_res_free); | |
2073 | ||
2074 | /** | |
2075 | * spi_res_add - add a spi_res to the spi_message | |
2076 | * @message: the spi message | |
2077 | * @res: the spi_resource | |
2078 | */ | |
2079 | void spi_res_add(struct spi_message *message, void *res) | |
2080 | { | |
2081 | struct spi_res *sres = container_of(res, struct spi_res, data); | |
2082 | ||
2083 | WARN_ON(!list_empty(&sres->entry)); | |
2084 | list_add_tail(&sres->entry, &message->resources); | |
2085 | } | |
2086 | EXPORT_SYMBOL_GPL(spi_res_add); | |
2087 | ||
2088 | /** | |
2089 | * spi_res_release - release all spi resources for this message | |
2090 | * @master: the @spi_master | |
2091 | * @message: the @spi_message | |
2092 | */ | |
2093 | void spi_res_release(struct spi_master *master, | |
2094 | struct spi_message *message) | |
2095 | { | |
2096 | struct spi_res *res; | |
2097 | ||
2098 | while (!list_empty(&message->resources)) { | |
2099 | res = list_last_entry(&message->resources, | |
2100 | struct spi_res, entry); | |
2101 | ||
2102 | if (res->release) | |
2103 | res->release(master, message, res->data); | |
2104 | ||
2105 | list_del(&res->entry); | |
2106 | ||
2107 | kfree(res); | |
2108 | } | |
2109 | } | |
2110 | EXPORT_SYMBOL_GPL(spi_res_release); | |
8ae12a0d DB |
2111 | |
2112 | /*-------------------------------------------------------------------------*/ | |
2113 | ||
523baf5a MS |
2114 | /* Core methods for spi_message alterations */ |
2115 | ||
2116 | static void __spi_replace_transfers_release(struct spi_master *master, | |
2117 | struct spi_message *msg, | |
2118 | void *res) | |
2119 | { | |
2120 | struct spi_replaced_transfers *rxfer = res; | |
2121 | size_t i; | |
2122 | ||
2123 | /* call extra callback if requested */ | |
2124 | if (rxfer->release) | |
2125 | rxfer->release(master, msg, res); | |
2126 | ||
2127 | /* insert replaced transfers back into the message */ | |
2128 | list_splice(&rxfer->replaced_transfers, rxfer->replaced_after); | |
2129 | ||
2130 | /* remove the formerly inserted entries */ | |
2131 | for (i = 0; i < rxfer->inserted; i++) | |
2132 | list_del(&rxfer->inserted_transfers[i].transfer_list); | |
2133 | } | |
2134 | ||
2135 | /** | |
2136 | * spi_replace_transfers - replace transfers with several transfers | |
2137 | * and register change with spi_message.resources | |
2138 | * @msg: the spi_message we work upon | |
2139 | * @xfer_first: the first spi_transfer we want to replace | |
2140 | * @remove: number of transfers to remove | |
2141 | * @insert: the number of transfers we want to insert instead | |
2142 | * @release: extra release code necessary in some circumstances | |
2143 | * @extradatasize: extra data to allocate (with alignment guarantees | |
2144 | * of struct @spi_transfer) | |
05885397 | 2145 | * @gfp: gfp flags |
523baf5a MS |
2146 | * |
2147 | * Returns: pointer to @spi_replaced_transfers, | |
2148 | * PTR_ERR(...) in case of errors. | |
2149 | */ | |
2150 | struct spi_replaced_transfers *spi_replace_transfers( | |
2151 | struct spi_message *msg, | |
2152 | struct spi_transfer *xfer_first, | |
2153 | size_t remove, | |
2154 | size_t insert, | |
2155 | spi_replaced_release_t release, | |
2156 | size_t extradatasize, | |
2157 | gfp_t gfp) | |
2158 | { | |
2159 | struct spi_replaced_transfers *rxfer; | |
2160 | struct spi_transfer *xfer; | |
2161 | size_t i; | |
2162 | ||
2163 | /* allocate the structure using spi_res */ | |
2164 | rxfer = spi_res_alloc(msg->spi, __spi_replace_transfers_release, | |
2165 | insert * sizeof(struct spi_transfer) | |
2166 | + sizeof(struct spi_replaced_transfers) | |
2167 | + extradatasize, | |
2168 | gfp); | |
2169 | if (!rxfer) | |
2170 | return ERR_PTR(-ENOMEM); | |
2171 | ||
2172 | /* the release code to invoke before running the generic release */ | |
2173 | rxfer->release = release; | |
2174 | ||
2175 | /* assign extradata */ | |
2176 | if (extradatasize) | |
2177 | rxfer->extradata = | |
2178 | &rxfer->inserted_transfers[insert]; | |
2179 | ||
2180 | /* init the replaced_transfers list */ | |
2181 | INIT_LIST_HEAD(&rxfer->replaced_transfers); | |
2182 | ||
2183 | /* assign the list_entry after which we should reinsert | |
2184 | * the @replaced_transfers - it may be spi_message.messages! | |
2185 | */ | |
2186 | rxfer->replaced_after = xfer_first->transfer_list.prev; | |
2187 | ||
2188 | /* remove the requested number of transfers */ | |
2189 | for (i = 0; i < remove; i++) { | |
2190 | /* if the entry after replaced_after it is msg->transfers | |
2191 | * then we have been requested to remove more transfers | |
2192 | * than are in the list | |
2193 | */ | |
2194 | if (rxfer->replaced_after->next == &msg->transfers) { | |
2195 | dev_err(&msg->spi->dev, | |
2196 | "requested to remove more spi_transfers than are available\n"); | |
2197 | /* insert replaced transfers back into the message */ | |
2198 | list_splice(&rxfer->replaced_transfers, | |
2199 | rxfer->replaced_after); | |
2200 | ||
2201 | /* free the spi_replace_transfer structure */ | |
2202 | spi_res_free(rxfer); | |
2203 | ||
2204 | /* and return with an error */ | |
2205 | return ERR_PTR(-EINVAL); | |
2206 | } | |
2207 | ||
2208 | /* remove the entry after replaced_after from list of | |
2209 | * transfers and add it to list of replaced_transfers | |
2210 | */ | |
2211 | list_move_tail(rxfer->replaced_after->next, | |
2212 | &rxfer->replaced_transfers); | |
2213 | } | |
2214 | ||
2215 | /* create copy of the given xfer with identical settings | |
2216 | * based on the first transfer to get removed | |
2217 | */ | |
2218 | for (i = 0; i < insert; i++) { | |
2219 | /* we need to run in reverse order */ | |
2220 | xfer = &rxfer->inserted_transfers[insert - 1 - i]; | |
2221 | ||
2222 | /* copy all spi_transfer data */ | |
2223 | memcpy(xfer, xfer_first, sizeof(*xfer)); | |
2224 | ||
2225 | /* add to list */ | |
2226 | list_add(&xfer->transfer_list, rxfer->replaced_after); | |
2227 | ||
2228 | /* clear cs_change and delay_usecs for all but the last */ | |
2229 | if (i) { | |
2230 | xfer->cs_change = false; | |
2231 | xfer->delay_usecs = 0; | |
2232 | } | |
2233 | } | |
2234 | ||
2235 | /* set up inserted */ | |
2236 | rxfer->inserted = insert; | |
2237 | ||
2238 | /* and register it with spi_res/spi_message */ | |
2239 | spi_res_add(msg, rxfer); | |
2240 | ||
2241 | return rxfer; | |
2242 | } | |
2243 | EXPORT_SYMBOL_GPL(spi_replace_transfers); | |
2244 | ||
08933418 FE |
2245 | static int __spi_split_transfer_maxsize(struct spi_master *master, |
2246 | struct spi_message *msg, | |
2247 | struct spi_transfer **xferp, | |
2248 | size_t maxsize, | |
2249 | gfp_t gfp) | |
d9f12122 MS |
2250 | { |
2251 | struct spi_transfer *xfer = *xferp, *xfers; | |
2252 | struct spi_replaced_transfers *srt; | |
2253 | size_t offset; | |
2254 | size_t count, i; | |
2255 | ||
2256 | /* warn once about this fact that we are splitting a transfer */ | |
2257 | dev_warn_once(&msg->spi->dev, | |
7d62f51e | 2258 | "spi_transfer of length %i exceed max length of %zu - needed to split transfers\n", |
d9f12122 MS |
2259 | xfer->len, maxsize); |
2260 | ||
2261 | /* calculate how many we have to replace */ | |
2262 | count = DIV_ROUND_UP(xfer->len, maxsize); | |
2263 | ||
2264 | /* create replacement */ | |
2265 | srt = spi_replace_transfers(msg, xfer, 1, count, NULL, 0, gfp); | |
657d32ef DC |
2266 | if (IS_ERR(srt)) |
2267 | return PTR_ERR(srt); | |
d9f12122 MS |
2268 | xfers = srt->inserted_transfers; |
2269 | ||
2270 | /* now handle each of those newly inserted spi_transfers | |
2271 | * note that the replacements spi_transfers all are preset | |
2272 | * to the same values as *xferp, so tx_buf, rx_buf and len | |
2273 | * are all identical (as well as most others) | |
2274 | * so we just have to fix up len and the pointers. | |
2275 | * | |
2276 | * this also includes support for the depreciated | |
2277 | * spi_message.is_dma_mapped interface | |
2278 | */ | |
2279 | ||
2280 | /* the first transfer just needs the length modified, so we | |
2281 | * run it outside the loop | |
2282 | */ | |
c8dab77a | 2283 | xfers[0].len = min_t(size_t, maxsize, xfer[0].len); |
d9f12122 MS |
2284 | |
2285 | /* all the others need rx_buf/tx_buf also set */ | |
2286 | for (i = 1, offset = maxsize; i < count; offset += maxsize, i++) { | |
2287 | /* update rx_buf, tx_buf and dma */ | |
2288 | if (xfers[i].rx_buf) | |
2289 | xfers[i].rx_buf += offset; | |
2290 | if (xfers[i].rx_dma) | |
2291 | xfers[i].rx_dma += offset; | |
2292 | if (xfers[i].tx_buf) | |
2293 | xfers[i].tx_buf += offset; | |
2294 | if (xfers[i].tx_dma) | |
2295 | xfers[i].tx_dma += offset; | |
2296 | ||
2297 | /* update length */ | |
2298 | xfers[i].len = min(maxsize, xfers[i].len - offset); | |
2299 | } | |
2300 | ||
2301 | /* we set up xferp to the last entry we have inserted, | |
2302 | * so that we skip those already split transfers | |
2303 | */ | |
2304 | *xferp = &xfers[count - 1]; | |
2305 | ||
2306 | /* increment statistics counters */ | |
2307 | SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, | |
2308 | transfers_split_maxsize); | |
2309 | SPI_STATISTICS_INCREMENT_FIELD(&msg->spi->statistics, | |
2310 | transfers_split_maxsize); | |
2311 | ||
2312 | return 0; | |
2313 | } | |
2314 | ||
2315 | /** | |
2316 | * spi_split_tranfers_maxsize - split spi transfers into multiple transfers | |
2317 | * when an individual transfer exceeds a | |
2318 | * certain size | |
2319 | * @master: the @spi_master for this transfer | |
3700ce95 MI |
2320 | * @msg: the @spi_message to transform |
2321 | * @maxsize: the maximum when to apply this | |
d9f12122 MS |
2322 | * |
2323 | * Return: status of transformation | |
2324 | */ | |
2325 | int spi_split_transfers_maxsize(struct spi_master *master, | |
2326 | struct spi_message *msg, | |
2327 | size_t maxsize, | |
2328 | gfp_t gfp) | |
2329 | { | |
2330 | struct spi_transfer *xfer; | |
2331 | int ret; | |
2332 | ||
2333 | /* iterate over the transfer_list, | |
2334 | * but note that xfer is advanced to the last transfer inserted | |
2335 | * to avoid checking sizes again unnecessarily (also xfer does | |
2336 | * potentiall belong to a different list by the time the | |
2337 | * replacement has happened | |
2338 | */ | |
2339 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | |
2340 | if (xfer->len > maxsize) { | |
2341 | ret = __spi_split_transfer_maxsize( | |
2342 | master, msg, &xfer, maxsize, gfp); | |
2343 | if (ret) | |
2344 | return ret; | |
2345 | } | |
2346 | } | |
2347 | ||
2348 | return 0; | |
2349 | } | |
2350 | EXPORT_SYMBOL_GPL(spi_split_transfers_maxsize); | |
2351 | ||
523baf5a MS |
2352 | /*-------------------------------------------------------------------------*/ |
2353 | ||
7d077197 DB |
2354 | /* Core methods for SPI master protocol drivers. Some of the |
2355 | * other core methods are currently defined as inline functions. | |
2356 | */ | |
2357 | ||
63ab645f SB |
2358 | static int __spi_validate_bits_per_word(struct spi_master *master, u8 bits_per_word) |
2359 | { | |
2360 | if (master->bits_per_word_mask) { | |
2361 | /* Only 32 bits fit in the mask */ | |
2362 | if (bits_per_word > 32) | |
2363 | return -EINVAL; | |
2364 | if (!(master->bits_per_word_mask & | |
2365 | SPI_BPW_MASK(bits_per_word))) | |
2366 | return -EINVAL; | |
2367 | } | |
2368 | ||
2369 | return 0; | |
2370 | } | |
2371 | ||
7d077197 DB |
2372 | /** |
2373 | * spi_setup - setup SPI mode and clock rate | |
2374 | * @spi: the device whose settings are being modified | |
2375 | * Context: can sleep, and no requests are queued to the device | |
2376 | * | |
2377 | * SPI protocol drivers may need to update the transfer mode if the | |
2378 | * device doesn't work with its default. They may likewise need | |
2379 | * to update clock rates or word sizes from initial values. This function | |
2380 | * changes those settings, and must be called from a context that can sleep. | |
2381 | * Except for SPI_CS_HIGH, which takes effect immediately, the changes take | |
2382 | * effect the next time the device is selected and data is transferred to | |
2383 | * or from it. When this function returns, the spi device is deselected. | |
2384 | * | |
2385 | * Note that this call will fail if the protocol driver specifies an option | |
2386 | * that the underlying controller or its driver does not support. For | |
2387 | * example, not all hardware supports wire transfers using nine bit words, | |
2388 | * LSB-first wire encoding, or active-high chipselects. | |
97d56dc6 JMC |
2389 | * |
2390 | * Return: zero on success, else a negative error code. | |
7d077197 DB |
2391 | */ |
2392 | int spi_setup(struct spi_device *spi) | |
2393 | { | |
83596fbe | 2394 | unsigned bad_bits, ugly_bits; |
5ab8d262 | 2395 | int status; |
7d077197 | 2396 | |
f477b7fb | 2397 | /* check mode to prevent that DUAL and QUAD set at the same time |
2398 | */ | |
2399 | if (((spi->mode & SPI_TX_DUAL) && (spi->mode & SPI_TX_QUAD)) || | |
2400 | ((spi->mode & SPI_RX_DUAL) && (spi->mode & SPI_RX_QUAD))) { | |
2401 | dev_err(&spi->dev, | |
2402 | "setup: can not select dual and quad at the same time\n"); | |
2403 | return -EINVAL; | |
2404 | } | |
2405 | /* if it is SPI_3WIRE mode, DUAL and QUAD should be forbidden | |
2406 | */ | |
2407 | if ((spi->mode & SPI_3WIRE) && (spi->mode & | |
2408 | (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD))) | |
2409 | return -EINVAL; | |
e7db06b5 DB |
2410 | /* help drivers fail *cleanly* when they need options |
2411 | * that aren't supported with their current master | |
2412 | */ | |
2413 | bad_bits = spi->mode & ~spi->master->mode_bits; | |
83596fbe GU |
2414 | ugly_bits = bad_bits & |
2415 | (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD); | |
2416 | if (ugly_bits) { | |
2417 | dev_warn(&spi->dev, | |
2418 | "setup: ignoring unsupported mode bits %x\n", | |
2419 | ugly_bits); | |
2420 | spi->mode &= ~ugly_bits; | |
2421 | bad_bits &= ~ugly_bits; | |
2422 | } | |
e7db06b5 | 2423 | if (bad_bits) { |
eb288a1f | 2424 | dev_err(&spi->dev, "setup: unsupported mode bits %x\n", |
e7db06b5 DB |
2425 | bad_bits); |
2426 | return -EINVAL; | |
2427 | } | |
2428 | ||
7d077197 DB |
2429 | if (!spi->bits_per_word) |
2430 | spi->bits_per_word = 8; | |
2431 | ||
5ab8d262 AS |
2432 | status = __spi_validate_bits_per_word(spi->master, spi->bits_per_word); |
2433 | if (status) | |
2434 | return status; | |
63ab645f | 2435 | |
052eb2d4 AL |
2436 | if (!spi->max_speed_hz) |
2437 | spi->max_speed_hz = spi->master->max_speed_hz; | |
2438 | ||
caae070c LD |
2439 | if (spi->master->setup) |
2440 | status = spi->master->setup(spi); | |
7d077197 | 2441 | |
abeedb01 FCJ |
2442 | spi_set_cs(spi, false); |
2443 | ||
5fe5f05e | 2444 | dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n", |
7d077197 DB |
2445 | (int) (spi->mode & (SPI_CPOL | SPI_CPHA)), |
2446 | (spi->mode & SPI_CS_HIGH) ? "cs_high, " : "", | |
2447 | (spi->mode & SPI_LSB_FIRST) ? "lsb, " : "", | |
2448 | (spi->mode & SPI_3WIRE) ? "3wire, " : "", | |
2449 | (spi->mode & SPI_LOOP) ? "loopback, " : "", | |
2450 | spi->bits_per_word, spi->max_speed_hz, | |
2451 | status); | |
2452 | ||
2453 | return status; | |
2454 | } | |
2455 | EXPORT_SYMBOL_GPL(spi_setup); | |
2456 | ||
90808738 | 2457 | static int __spi_validate(struct spi_device *spi, struct spi_message *message) |
cf32b71e ES |
2458 | { |
2459 | struct spi_master *master = spi->master; | |
e6811d1d | 2460 | struct spi_transfer *xfer; |
6ea31293 | 2461 | int w_size; |
cf32b71e | 2462 | |
24a0013a MB |
2463 | if (list_empty(&message->transfers)) |
2464 | return -EINVAL; | |
24a0013a | 2465 | |
cf32b71e ES |
2466 | /* Half-duplex links include original MicroWire, and ones with |
2467 | * only one data pin like SPI_3WIRE (switches direction) or where | |
2468 | * either MOSI or MISO is missing. They can also be caused by | |
2469 | * software limitations. | |
2470 | */ | |
2471 | if ((master->flags & SPI_MASTER_HALF_DUPLEX) | |
2472 | || (spi->mode & SPI_3WIRE)) { | |
cf32b71e ES |
2473 | unsigned flags = master->flags; |
2474 | ||
2475 | list_for_each_entry(xfer, &message->transfers, transfer_list) { | |
2476 | if (xfer->rx_buf && xfer->tx_buf) | |
2477 | return -EINVAL; | |
2478 | if ((flags & SPI_MASTER_NO_TX) && xfer->tx_buf) | |
2479 | return -EINVAL; | |
2480 | if ((flags & SPI_MASTER_NO_RX) && xfer->rx_buf) | |
2481 | return -EINVAL; | |
2482 | } | |
2483 | } | |
2484 | ||
e6811d1d | 2485 | /** |
059b8ffe LD |
2486 | * Set transfer bits_per_word and max speed as spi device default if |
2487 | * it is not set for this transfer. | |
f477b7fb | 2488 | * Set transfer tx_nbits and rx_nbits as single transfer default |
2489 | * (SPI_NBITS_SINGLE) if it is not set for this transfer. | |
e6811d1d | 2490 | */ |
77e80588 | 2491 | message->frame_length = 0; |
e6811d1d | 2492 | list_for_each_entry(xfer, &message->transfers, transfer_list) { |
078726ce | 2493 | message->frame_length += xfer->len; |
e6811d1d LD |
2494 | if (!xfer->bits_per_word) |
2495 | xfer->bits_per_word = spi->bits_per_word; | |
a6f87fad AL |
2496 | |
2497 | if (!xfer->speed_hz) | |
059b8ffe | 2498 | xfer->speed_hz = spi->max_speed_hz; |
7dc9fbc3 MB |
2499 | if (!xfer->speed_hz) |
2500 | xfer->speed_hz = master->max_speed_hz; | |
a6f87fad AL |
2501 | |
2502 | if (master->max_speed_hz && | |
2503 | xfer->speed_hz > master->max_speed_hz) | |
2504 | xfer->speed_hz = master->max_speed_hz; | |
56ede94a | 2505 | |
63ab645f SB |
2506 | if (__spi_validate_bits_per_word(master, xfer->bits_per_word)) |
2507 | return -EINVAL; | |
a2fd4f9f | 2508 | |
4d94bd21 II |
2509 | /* |
2510 | * SPI transfer length should be multiple of SPI word size | |
2511 | * where SPI word size should be power-of-two multiple | |
2512 | */ | |
2513 | if (xfer->bits_per_word <= 8) | |
2514 | w_size = 1; | |
2515 | else if (xfer->bits_per_word <= 16) | |
2516 | w_size = 2; | |
2517 | else | |
2518 | w_size = 4; | |
2519 | ||
4d94bd21 | 2520 | /* No partial transfers accepted */ |
6ea31293 | 2521 | if (xfer->len % w_size) |
4d94bd21 II |
2522 | return -EINVAL; |
2523 | ||
a2fd4f9f MB |
2524 | if (xfer->speed_hz && master->min_speed_hz && |
2525 | xfer->speed_hz < master->min_speed_hz) | |
2526 | return -EINVAL; | |
f477b7fb | 2527 | |
2528 | if (xfer->tx_buf && !xfer->tx_nbits) | |
2529 | xfer->tx_nbits = SPI_NBITS_SINGLE; | |
2530 | if (xfer->rx_buf && !xfer->rx_nbits) | |
2531 | xfer->rx_nbits = SPI_NBITS_SINGLE; | |
2532 | /* check transfer tx/rx_nbits: | |
1afd9989 GU |
2533 | * 1. check the value matches one of single, dual and quad |
2534 | * 2. check tx/rx_nbits match the mode in spi_device | |
f477b7fb | 2535 | */ |
db90a441 SP |
2536 | if (xfer->tx_buf) { |
2537 | if (xfer->tx_nbits != SPI_NBITS_SINGLE && | |
2538 | xfer->tx_nbits != SPI_NBITS_DUAL && | |
2539 | xfer->tx_nbits != SPI_NBITS_QUAD) | |
2540 | return -EINVAL; | |
2541 | if ((xfer->tx_nbits == SPI_NBITS_DUAL) && | |
2542 | !(spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD))) | |
2543 | return -EINVAL; | |
2544 | if ((xfer->tx_nbits == SPI_NBITS_QUAD) && | |
2545 | !(spi->mode & SPI_TX_QUAD)) | |
2546 | return -EINVAL; | |
db90a441 | 2547 | } |
f477b7fb | 2548 | /* check transfer rx_nbits */ |
db90a441 SP |
2549 | if (xfer->rx_buf) { |
2550 | if (xfer->rx_nbits != SPI_NBITS_SINGLE && | |
2551 | xfer->rx_nbits != SPI_NBITS_DUAL && | |
2552 | xfer->rx_nbits != SPI_NBITS_QUAD) | |
2553 | return -EINVAL; | |
2554 | if ((xfer->rx_nbits == SPI_NBITS_DUAL) && | |
2555 | !(spi->mode & (SPI_RX_DUAL | SPI_RX_QUAD))) | |
2556 | return -EINVAL; | |
2557 | if ((xfer->rx_nbits == SPI_NBITS_QUAD) && | |
2558 | !(spi->mode & SPI_RX_QUAD)) | |
2559 | return -EINVAL; | |
db90a441 | 2560 | } |
e6811d1d LD |
2561 | } |
2562 | ||
cf32b71e | 2563 | message->status = -EINPROGRESS; |
90808738 MB |
2564 | |
2565 | return 0; | |
2566 | } | |
2567 | ||
2568 | static int __spi_async(struct spi_device *spi, struct spi_message *message) | |
2569 | { | |
2570 | struct spi_master *master = spi->master; | |
2571 | ||
2572 | message->spi = spi; | |
2573 | ||
eca2ebc7 MS |
2574 | SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, spi_async); |
2575 | SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_async); | |
2576 | ||
90808738 MB |
2577 | trace_spi_message_submit(message); |
2578 | ||
cf32b71e ES |
2579 | return master->transfer(spi, message); |
2580 | } | |
2581 | ||
568d0697 DB |
2582 | /** |
2583 | * spi_async - asynchronous SPI transfer | |
2584 | * @spi: device with which data will be exchanged | |
2585 | * @message: describes the data transfers, including completion callback | |
2586 | * Context: any (irqs may be blocked, etc) | |
2587 | * | |
2588 | * This call may be used in_irq and other contexts which can't sleep, | |
2589 | * as well as from task contexts which can sleep. | |
2590 | * | |
2591 | * The completion callback is invoked in a context which can't sleep. | |
2592 | * Before that invocation, the value of message->status is undefined. | |
2593 | * When the callback is issued, message->status holds either zero (to | |
2594 | * indicate complete success) or a negative error code. After that | |
2595 | * callback returns, the driver which issued the transfer request may | |
2596 | * deallocate the associated memory; it's no longer in use by any SPI | |
2597 | * core or controller driver code. | |
2598 | * | |
2599 | * Note that although all messages to a spi_device are handled in | |
2600 | * FIFO order, messages may go to different devices in other orders. | |
2601 | * Some device might be higher priority, or have various "hard" access | |
2602 | * time requirements, for example. | |
2603 | * | |
2604 | * On detection of any fault during the transfer, processing of | |
2605 | * the entire message is aborted, and the device is deselected. | |
2606 | * Until returning from the associated message completion callback, | |
2607 | * no other spi_message queued to that device will be processed. | |
2608 | * (This rule applies equally to all the synchronous transfer calls, | |
2609 | * which are wrappers around this core asynchronous primitive.) | |
97d56dc6 JMC |
2610 | * |
2611 | * Return: zero on success, else a negative error code. | |
568d0697 DB |
2612 | */ |
2613 | int spi_async(struct spi_device *spi, struct spi_message *message) | |
2614 | { | |
2615 | struct spi_master *master = spi->master; | |
cf32b71e ES |
2616 | int ret; |
2617 | unsigned long flags; | |
568d0697 | 2618 | |
90808738 MB |
2619 | ret = __spi_validate(spi, message); |
2620 | if (ret != 0) | |
2621 | return ret; | |
2622 | ||
cf32b71e | 2623 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); |
568d0697 | 2624 | |
cf32b71e ES |
2625 | if (master->bus_lock_flag) |
2626 | ret = -EBUSY; | |
2627 | else | |
2628 | ret = __spi_async(spi, message); | |
568d0697 | 2629 | |
cf32b71e ES |
2630 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); |
2631 | ||
2632 | return ret; | |
568d0697 DB |
2633 | } |
2634 | EXPORT_SYMBOL_GPL(spi_async); | |
2635 | ||
cf32b71e ES |
2636 | /** |
2637 | * spi_async_locked - version of spi_async with exclusive bus usage | |
2638 | * @spi: device with which data will be exchanged | |
2639 | * @message: describes the data transfers, including completion callback | |
2640 | * Context: any (irqs may be blocked, etc) | |
2641 | * | |
2642 | * This call may be used in_irq and other contexts which can't sleep, | |
2643 | * as well as from task contexts which can sleep. | |
2644 | * | |
2645 | * The completion callback is invoked in a context which can't sleep. | |
2646 | * Before that invocation, the value of message->status is undefined. | |
2647 | * When the callback is issued, message->status holds either zero (to | |
2648 | * indicate complete success) or a negative error code. After that | |
2649 | * callback returns, the driver which issued the transfer request may | |
2650 | * deallocate the associated memory; it's no longer in use by any SPI | |
2651 | * core or controller driver code. | |
2652 | * | |
2653 | * Note that although all messages to a spi_device are handled in | |
2654 | * FIFO order, messages may go to different devices in other orders. | |
2655 | * Some device might be higher priority, or have various "hard" access | |
2656 | * time requirements, for example. | |
2657 | * | |
2658 | * On detection of any fault during the transfer, processing of | |
2659 | * the entire message is aborted, and the device is deselected. | |
2660 | * Until returning from the associated message completion callback, | |
2661 | * no other spi_message queued to that device will be processed. | |
2662 | * (This rule applies equally to all the synchronous transfer calls, | |
2663 | * which are wrappers around this core asynchronous primitive.) | |
97d56dc6 JMC |
2664 | * |
2665 | * Return: zero on success, else a negative error code. | |
cf32b71e ES |
2666 | */ |
2667 | int spi_async_locked(struct spi_device *spi, struct spi_message *message) | |
2668 | { | |
2669 | struct spi_master *master = spi->master; | |
2670 | int ret; | |
2671 | unsigned long flags; | |
2672 | ||
90808738 MB |
2673 | ret = __spi_validate(spi, message); |
2674 | if (ret != 0) | |
2675 | return ret; | |
2676 | ||
cf32b71e ES |
2677 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); |
2678 | ||
2679 | ret = __spi_async(spi, message); | |
2680 | ||
2681 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); | |
2682 | ||
2683 | return ret; | |
2684 | ||
2685 | } | |
2686 | EXPORT_SYMBOL_GPL(spi_async_locked); | |
2687 | ||
7d077197 DB |
2688 | |
2689 | /*-------------------------------------------------------------------------*/ | |
2690 | ||
2691 | /* Utility methods for SPI master protocol drivers, layered on | |
2692 | * top of the core. Some other utility methods are defined as | |
2693 | * inline functions. | |
2694 | */ | |
2695 | ||
5d870c8e AM |
2696 | static void spi_complete(void *arg) |
2697 | { | |
2698 | complete(arg); | |
2699 | } | |
2700 | ||
cf32b71e ES |
2701 | static int __spi_sync(struct spi_device *spi, struct spi_message *message, |
2702 | int bus_locked) | |
2703 | { | |
2704 | DECLARE_COMPLETION_ONSTACK(done); | |
2705 | int status; | |
2706 | struct spi_master *master = spi->master; | |
0461a414 MB |
2707 | unsigned long flags; |
2708 | ||
2709 | status = __spi_validate(spi, message); | |
2710 | if (status != 0) | |
2711 | return status; | |
cf32b71e ES |
2712 | |
2713 | message->complete = spi_complete; | |
2714 | message->context = &done; | |
0461a414 | 2715 | message->spi = spi; |
cf32b71e | 2716 | |
eca2ebc7 MS |
2717 | SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, spi_sync); |
2718 | SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_sync); | |
2719 | ||
cf32b71e ES |
2720 | if (!bus_locked) |
2721 | mutex_lock(&master->bus_lock_mutex); | |
2722 | ||
0461a414 MB |
2723 | /* If we're not using the legacy transfer method then we will |
2724 | * try to transfer in the calling context so special case. | |
2725 | * This code would be less tricky if we could remove the | |
2726 | * support for driver implemented message queues. | |
2727 | */ | |
2728 | if (master->transfer == spi_queued_transfer) { | |
2729 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); | |
2730 | ||
2731 | trace_spi_message_submit(message); | |
2732 | ||
2733 | status = __spi_queued_transfer(spi, message, false); | |
2734 | ||
2735 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); | |
2736 | } else { | |
2737 | status = spi_async_locked(spi, message); | |
2738 | } | |
cf32b71e ES |
2739 | |
2740 | if (!bus_locked) | |
2741 | mutex_unlock(&master->bus_lock_mutex); | |
2742 | ||
2743 | if (status == 0) { | |
0461a414 MB |
2744 | /* Push out the messages in the calling context if we |
2745 | * can. | |
2746 | */ | |
eca2ebc7 MS |
2747 | if (master->transfer == spi_queued_transfer) { |
2748 | SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, | |
2749 | spi_sync_immediate); | |
2750 | SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, | |
2751 | spi_sync_immediate); | |
fc9e0f71 | 2752 | __spi_pump_messages(master, false); |
eca2ebc7 | 2753 | } |
0461a414 | 2754 | |
cf32b71e ES |
2755 | wait_for_completion(&done); |
2756 | status = message->status; | |
2757 | } | |
2758 | message->context = NULL; | |
2759 | return status; | |
2760 | } | |
2761 | ||
8ae12a0d DB |
2762 | /** |
2763 | * spi_sync - blocking/synchronous SPI data transfers | |
2764 | * @spi: device with which data will be exchanged | |
2765 | * @message: describes the data transfers | |
33e34dc6 | 2766 | * Context: can sleep |
8ae12a0d DB |
2767 | * |
2768 | * This call may only be used from a context that may sleep. The sleep | |
2769 | * is non-interruptible, and has no timeout. Low-overhead controller | |
2770 | * drivers may DMA directly into and out of the message buffers. | |
2771 | * | |
2772 | * Note that the SPI device's chip select is active during the message, | |
2773 | * and then is normally disabled between messages. Drivers for some | |
2774 | * frequently-used devices may want to minimize costs of selecting a chip, | |
2775 | * by leaving it selected in anticipation that the next message will go | |
2776 | * to the same chip. (That may increase power usage.) | |
2777 | * | |
0c868461 DB |
2778 | * Also, the caller is guaranteeing that the memory associated with the |
2779 | * message will not be freed before this call returns. | |
2780 | * | |
97d56dc6 | 2781 | * Return: zero on success, else a negative error code. |
8ae12a0d DB |
2782 | */ |
2783 | int spi_sync(struct spi_device *spi, struct spi_message *message) | |
2784 | { | |
cf32b71e | 2785 | return __spi_sync(spi, message, 0); |
8ae12a0d DB |
2786 | } |
2787 | EXPORT_SYMBOL_GPL(spi_sync); | |
2788 | ||
cf32b71e ES |
2789 | /** |
2790 | * spi_sync_locked - version of spi_sync with exclusive bus usage | |
2791 | * @spi: device with which data will be exchanged | |
2792 | * @message: describes the data transfers | |
2793 | * Context: can sleep | |
2794 | * | |
2795 | * This call may only be used from a context that may sleep. The sleep | |
2796 | * is non-interruptible, and has no timeout. Low-overhead controller | |
2797 | * drivers may DMA directly into and out of the message buffers. | |
2798 | * | |
2799 | * This call should be used by drivers that require exclusive access to the | |
25985edc | 2800 | * SPI bus. It has to be preceded by a spi_bus_lock call. The SPI bus must |
cf32b71e ES |
2801 | * be released by a spi_bus_unlock call when the exclusive access is over. |
2802 | * | |
97d56dc6 | 2803 | * Return: zero on success, else a negative error code. |
cf32b71e ES |
2804 | */ |
2805 | int spi_sync_locked(struct spi_device *spi, struct spi_message *message) | |
2806 | { | |
2807 | return __spi_sync(spi, message, 1); | |
2808 | } | |
2809 | EXPORT_SYMBOL_GPL(spi_sync_locked); | |
2810 | ||
2811 | /** | |
2812 | * spi_bus_lock - obtain a lock for exclusive SPI bus usage | |
2813 | * @master: SPI bus master that should be locked for exclusive bus access | |
2814 | * Context: can sleep | |
2815 | * | |
2816 | * This call may only be used from a context that may sleep. The sleep | |
2817 | * is non-interruptible, and has no timeout. | |
2818 | * | |
2819 | * This call should be used by drivers that require exclusive access to the | |
2820 | * SPI bus. The SPI bus must be released by a spi_bus_unlock call when the | |
2821 | * exclusive access is over. Data transfer must be done by spi_sync_locked | |
2822 | * and spi_async_locked calls when the SPI bus lock is held. | |
2823 | * | |
97d56dc6 | 2824 | * Return: always zero. |
cf32b71e ES |
2825 | */ |
2826 | int spi_bus_lock(struct spi_master *master) | |
2827 | { | |
2828 | unsigned long flags; | |
2829 | ||
2830 | mutex_lock(&master->bus_lock_mutex); | |
2831 | ||
2832 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); | |
2833 | master->bus_lock_flag = 1; | |
2834 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); | |
2835 | ||
2836 | /* mutex remains locked until spi_bus_unlock is called */ | |
2837 | ||
2838 | return 0; | |
2839 | } | |
2840 | EXPORT_SYMBOL_GPL(spi_bus_lock); | |
2841 | ||
2842 | /** | |
2843 | * spi_bus_unlock - release the lock for exclusive SPI bus usage | |
2844 | * @master: SPI bus master that was locked for exclusive bus access | |
2845 | * Context: can sleep | |
2846 | * | |
2847 | * This call may only be used from a context that may sleep. The sleep | |
2848 | * is non-interruptible, and has no timeout. | |
2849 | * | |
2850 | * This call releases an SPI bus lock previously obtained by an spi_bus_lock | |
2851 | * call. | |
2852 | * | |
97d56dc6 | 2853 | * Return: always zero. |
cf32b71e ES |
2854 | */ |
2855 | int spi_bus_unlock(struct spi_master *master) | |
2856 | { | |
2857 | master->bus_lock_flag = 0; | |
2858 | ||
2859 | mutex_unlock(&master->bus_lock_mutex); | |
2860 | ||
2861 | return 0; | |
2862 | } | |
2863 | EXPORT_SYMBOL_GPL(spi_bus_unlock); | |
2864 | ||
a9948b61 | 2865 | /* portable code must never pass more than 32 bytes */ |
5fe5f05e | 2866 | #define SPI_BUFSIZ max(32, SMP_CACHE_BYTES) |
8ae12a0d DB |
2867 | |
2868 | static u8 *buf; | |
2869 | ||
2870 | /** | |
2871 | * spi_write_then_read - SPI synchronous write followed by read | |
2872 | * @spi: device with which data will be exchanged | |
2873 | * @txbuf: data to be written (need not be dma-safe) | |
2874 | * @n_tx: size of txbuf, in bytes | |
27570497 JP |
2875 | * @rxbuf: buffer into which data will be read (need not be dma-safe) |
2876 | * @n_rx: size of rxbuf, in bytes | |
33e34dc6 | 2877 | * Context: can sleep |
8ae12a0d DB |
2878 | * |
2879 | * This performs a half duplex MicroWire style transaction with the | |
2880 | * device, sending txbuf and then reading rxbuf. The return value | |
2881 | * is zero for success, else a negative errno status code. | |
b885244e | 2882 | * This call may only be used from a context that may sleep. |
8ae12a0d | 2883 | * |
0c868461 | 2884 | * Parameters to this routine are always copied using a small buffer; |
33e34dc6 DB |
2885 | * portable code should never use this for more than 32 bytes. |
2886 | * Performance-sensitive or bulk transfer code should instead use | |
0c868461 | 2887 | * spi_{async,sync}() calls with dma-safe buffers. |
97d56dc6 JMC |
2888 | * |
2889 | * Return: zero on success, else a negative error code. | |
8ae12a0d DB |
2890 | */ |
2891 | int spi_write_then_read(struct spi_device *spi, | |
0c4a1590 MB |
2892 | const void *txbuf, unsigned n_tx, |
2893 | void *rxbuf, unsigned n_rx) | |
8ae12a0d | 2894 | { |
068f4070 | 2895 | static DEFINE_MUTEX(lock); |
8ae12a0d DB |
2896 | |
2897 | int status; | |
2898 | struct spi_message message; | |
bdff549e | 2899 | struct spi_transfer x[2]; |
8ae12a0d DB |
2900 | u8 *local_buf; |
2901 | ||
b3a223ee MB |
2902 | /* Use preallocated DMA-safe buffer if we can. We can't avoid |
2903 | * copying here, (as a pure convenience thing), but we can | |
2904 | * keep heap costs out of the hot path unless someone else is | |
2905 | * using the pre-allocated buffer or the transfer is too large. | |
8ae12a0d | 2906 | */ |
b3a223ee | 2907 | if ((n_tx + n_rx) > SPI_BUFSIZ || !mutex_trylock(&lock)) { |
2cd94c8a MB |
2908 | local_buf = kmalloc(max((unsigned)SPI_BUFSIZ, n_tx + n_rx), |
2909 | GFP_KERNEL | GFP_DMA); | |
b3a223ee MB |
2910 | if (!local_buf) |
2911 | return -ENOMEM; | |
2912 | } else { | |
2913 | local_buf = buf; | |
2914 | } | |
8ae12a0d | 2915 | |
8275c642 | 2916 | spi_message_init(&message); |
5fe5f05e | 2917 | memset(x, 0, sizeof(x)); |
bdff549e DB |
2918 | if (n_tx) { |
2919 | x[0].len = n_tx; | |
2920 | spi_message_add_tail(&x[0], &message); | |
2921 | } | |
2922 | if (n_rx) { | |
2923 | x[1].len = n_rx; | |
2924 | spi_message_add_tail(&x[1], &message); | |
2925 | } | |
8275c642 | 2926 | |
8ae12a0d | 2927 | memcpy(local_buf, txbuf, n_tx); |
bdff549e DB |
2928 | x[0].tx_buf = local_buf; |
2929 | x[1].rx_buf = local_buf + n_tx; | |
8ae12a0d DB |
2930 | |
2931 | /* do the i/o */ | |
8ae12a0d | 2932 | status = spi_sync(spi, &message); |
9b938b74 | 2933 | if (status == 0) |
bdff549e | 2934 | memcpy(rxbuf, x[1].rx_buf, n_rx); |
8ae12a0d | 2935 | |
bdff549e | 2936 | if (x[0].tx_buf == buf) |
068f4070 | 2937 | mutex_unlock(&lock); |
8ae12a0d DB |
2938 | else |
2939 | kfree(local_buf); | |
2940 | ||
2941 | return status; | |
2942 | } | |
2943 | EXPORT_SYMBOL_GPL(spi_write_then_read); | |
2944 | ||
2945 | /*-------------------------------------------------------------------------*/ | |
2946 | ||
ce79d54a PA |
2947 | #if IS_ENABLED(CONFIG_OF_DYNAMIC) |
2948 | static int __spi_of_device_match(struct device *dev, void *data) | |
2949 | { | |
2950 | return dev->of_node == data; | |
2951 | } | |
2952 | ||
2953 | /* must call put_device() when done with returned spi_device device */ | |
2954 | static struct spi_device *of_find_spi_device_by_node(struct device_node *node) | |
2955 | { | |
2956 | struct device *dev = bus_find_device(&spi_bus_type, NULL, node, | |
2957 | __spi_of_device_match); | |
2958 | return dev ? to_spi_device(dev) : NULL; | |
2959 | } | |
2960 | ||
2961 | static int __spi_of_master_match(struct device *dev, const void *data) | |
2962 | { | |
2963 | return dev->of_node == data; | |
2964 | } | |
2965 | ||
2966 | /* the spi masters are not using spi_bus, so we find it with another way */ | |
2967 | static struct spi_master *of_find_spi_master_by_node(struct device_node *node) | |
2968 | { | |
2969 | struct device *dev; | |
2970 | ||
2971 | dev = class_find_device(&spi_master_class, NULL, node, | |
2972 | __spi_of_master_match); | |
2973 | if (!dev) | |
2974 | return NULL; | |
2975 | ||
2976 | /* reference got in class_find_device */ | |
2977 | return container_of(dev, struct spi_master, dev); | |
2978 | } | |
2979 | ||
2980 | static int of_spi_notify(struct notifier_block *nb, unsigned long action, | |
2981 | void *arg) | |
2982 | { | |
2983 | struct of_reconfig_data *rd = arg; | |
2984 | struct spi_master *master; | |
2985 | struct spi_device *spi; | |
2986 | ||
2987 | switch (of_reconfig_get_state_change(action, arg)) { | |
2988 | case OF_RECONFIG_CHANGE_ADD: | |
2989 | master = of_find_spi_master_by_node(rd->dn->parent); | |
2990 | if (master == NULL) | |
2991 | return NOTIFY_OK; /* not for us */ | |
2992 | ||
bd6c1644 GU |
2993 | if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) { |
2994 | put_device(&master->dev); | |
2995 | return NOTIFY_OK; | |
2996 | } | |
2997 | ||
ce79d54a PA |
2998 | spi = of_register_spi_device(master, rd->dn); |
2999 | put_device(&master->dev); | |
3000 | ||
3001 | if (IS_ERR(spi)) { | |
3002 | pr_err("%s: failed to create for '%s'\n", | |
3003 | __func__, rd->dn->full_name); | |
3004 | return notifier_from_errno(PTR_ERR(spi)); | |
3005 | } | |
3006 | break; | |
3007 | ||
3008 | case OF_RECONFIG_CHANGE_REMOVE: | |
bd6c1644 GU |
3009 | /* already depopulated? */ |
3010 | if (!of_node_check_flag(rd->dn, OF_POPULATED)) | |
3011 | return NOTIFY_OK; | |
3012 | ||
ce79d54a PA |
3013 | /* find our device by node */ |
3014 | spi = of_find_spi_device_by_node(rd->dn); | |
3015 | if (spi == NULL) | |
3016 | return NOTIFY_OK; /* no? not meant for us */ | |
3017 | ||
3018 | /* unregister takes one ref away */ | |
3019 | spi_unregister_device(spi); | |
3020 | ||
3021 | /* and put the reference of the find */ | |
3022 | put_device(&spi->dev); | |
3023 | break; | |
3024 | } | |
3025 | ||
3026 | return NOTIFY_OK; | |
3027 | } | |
3028 | ||
3029 | static struct notifier_block spi_of_notifier = { | |
3030 | .notifier_call = of_spi_notify, | |
3031 | }; | |
3032 | #else /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ | |
3033 | extern struct notifier_block spi_of_notifier; | |
3034 | #endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ | |
3035 | ||
8ae12a0d DB |
3036 | static int __init spi_init(void) |
3037 | { | |
b885244e DB |
3038 | int status; |
3039 | ||
e94b1766 | 3040 | buf = kmalloc(SPI_BUFSIZ, GFP_KERNEL); |
b885244e DB |
3041 | if (!buf) { |
3042 | status = -ENOMEM; | |
3043 | goto err0; | |
3044 | } | |
3045 | ||
3046 | status = bus_register(&spi_bus_type); | |
3047 | if (status < 0) | |
3048 | goto err1; | |
8ae12a0d | 3049 | |
b885244e DB |
3050 | status = class_register(&spi_master_class); |
3051 | if (status < 0) | |
3052 | goto err2; | |
ce79d54a | 3053 | |
5267720e | 3054 | if (IS_ENABLED(CONFIG_OF_DYNAMIC)) |
ce79d54a PA |
3055 | WARN_ON(of_reconfig_notifier_register(&spi_of_notifier)); |
3056 | ||
8ae12a0d | 3057 | return 0; |
b885244e DB |
3058 | |
3059 | err2: | |
3060 | bus_unregister(&spi_bus_type); | |
3061 | err1: | |
3062 | kfree(buf); | |
3063 | buf = NULL; | |
3064 | err0: | |
3065 | return status; | |
8ae12a0d | 3066 | } |
b885244e | 3067 | |
8ae12a0d DB |
3068 | /* board_info is normally registered in arch_initcall(), |
3069 | * but even essential drivers wait till later | |
b885244e DB |
3070 | * |
3071 | * REVISIT only boardinfo really needs static linking. the rest (device and | |
3072 | * driver registration) _could_ be dynamically linked (modular) ... costs | |
3073 | * include needing to have boardinfo data structures be much more public. | |
8ae12a0d | 3074 | */ |
673c0c00 | 3075 | postcore_initcall(spi_init); |
8ae12a0d | 3076 |